diff --git a/packages/core/src/lib/valueAnchor.ts b/packages/core/src/lib/valueAnchor.ts
new file mode 100644
index 00000000..d760b84d
--- /dev/null
+++ b/packages/core/src/lib/valueAnchor.ts
@@ -0,0 +1,12 @@
+/** fieldJustify vocabulary; semantics documented at the schema field. */
+export type FieldJustify = 'L' | 'C' | 'R';
+
+/** Origin shift keeping the justified edge fixed for an extent change `delta`
+ *  (before minus after). Centre rounds half away from zero (half-up walks a
+ *  dot per widen/narrow toggle); `ftFlip` inverts for ^FT I/B's bar offset. */
+export function valueAnchorShift(justify: FieldJustify, delta: number, ftFlip: boolean): number {
+  if (justify === 'L') return ftFlip ? -delta : 0;
+  if (justify === 'R') return ftFlip ? 0 : delta;
+  const half = Math.sign(delta) * Math.round(Math.abs(delta) / 2);
+  return ftFlip ? -half : half;
+}
diff --git a/packages/core/src/lib/zplImportService.ts b/packages/core/src/lib/zplImportService.ts
index 3e1e35ce..b6a85ce2 100644
--- a/packages/core/src/lib/zplImportService.ts
+++ b/packages/core/src/lib/zplImportService.ts
@@ -7,6 +7,8 @@ import type { CustomFontMapping, LabelConfig } from "../types/LabelConfig";
 import type { PrinterProfile } from "../types/PrinterProfile";
 import type { LabelObject, Page } from "../types/Group";
 import { nextFreeFnNumber, uniqueVariableName, type Variable } from "../types/Variable";
+import { BARCODE_1D_TYPES } from "../registry";
+import { objectRotation } from "../registry/rotation";
 
 export interface ZplImportResult {
   labelConfig: Partial<LabelConfig>;
@@ -25,7 +27,13 @@ export interface ZplImportResult {
   mixedPageGeometry: boolean;
 }
 
-export function importZplText(zpl: string, dpmm: number): ZplImportResult {
+export interface ZplImportOptions {
+  /** Rotated visual footprint (dots), or null when unmeasurable. Enables the
+   *  ^FT+R barcode x-normalisation; headless callers omit it (x uncorrected). */
+  measureFootprint?: (obj: LabelObject) => { w: number; h: number } | null;
+}
+
+export function importZplText(zpl: string, dpmm: number, opts?: ZplImportOptions): ZplImportResult {
   // Single pass: stream-persistent state (^MU, ^CC/^CT/^CD, ^CI, ^CW/uploads,
   // ^CF/^BY, ^LH/^LT/^LR) carries across ^XA blocks, and the parser owns the
   // page boundaries (prefix-aware, unlike a literal ^XA split).
@@ -89,6 +97,17 @@ export function importZplText(zpl: string, dpmm: number): ZplImportResult {
     if (nameRemap.size > 0) {
       rewireBindings(page.objects, nameRemap);
     }
+    // ^FT + rotation N only: ^FO-z and the rotation interaction are spec-
+    // ambiguous, pending printer check (the branch's own FT+I math would even
+    // demand shift 0 for R). Text unshifted (import measurement fragile).
+    if (opts?.measureFootprint) {
+      for (const o of page.objects) {
+        if (o.fieldJustify !== "R" || o.positionType !== "FT" || !BARCODE_1D_TYPES.has(o.type)) continue;
+        if (objectRotation((o as { props: object }).props) !== "N") continue;
+        const fp = opts.measureFootprint(o);
+        if (fp) o.x -= fp.w;
+      }
+    }
     // A bare page (no ^XA wrapper) usually carries just fonts/profile. But a
     // wrapper-less paste of real fields also lands here; import those as a page
     // so they aren't silently dropped (no overlay: the wrapper-less source has
diff --git a/packages/core/src/lib/zplParser/context.ts b/packages/core/src/lib/zplParser/context.ts
index 8174cc83..e4cd0e6b 100644
--- a/packages/core/src/lib/zplParser/context.ts
+++ b/packages/core/src/lib/zplParser/context.ts
@@ -102,6 +102,8 @@ export interface DefaultsState {
   cfWidth: number;
   cfFontId: string | undefined;
   fwRotation: TextProps["rotation"];
+  /** ^FW z: default justification for fields whose ^FO/^FT omits z. */
+  fwJustify: "L" | "R";
   fbWidth: number;
   fbLines: number;
   fbSpacing: number;
@@ -273,6 +275,9 @@ export function resetFormatScopedState(s: ParserState): void {
   s.comment.fnNumber = null;
   s.comment.fnComment = undefined;
   s.field = freshFieldState();
+  // ^FW justify persists across ^XA (like fwRotation); a later page's first
+  // position-less field must inherit it, not the fresh-state 'L'.
+  s.field.justify = s.defaults.fwJustify;
   s.format.fhActive = false;
   resetFieldBlockDefaults(s.defaults);
 }
@@ -318,6 +323,7 @@ export function createParserState(): ParserState {
       cfWidth: 0,
       cfFontId: undefined,
       fwRotation: "N",
+      fwJustify: "L",
       fbWidth: 0,
       fbLines: 1,
       fbSpacing: 0,
diff --git a/packages/core/src/lib/zplParser/flushField.ts b/packages/core/src/lib/zplParser/flushField.ts
index b534a665..532927eb 100644
--- a/packages/core/src/lib/zplParser/flushField.ts
+++ b/packages/core/src/lib/zplParser/flushField.ts
@@ -6,6 +6,7 @@ import {
   markerOf,
   type Variable,
 } from "../../types/Variable";
+import type { LabelObject } from "../../types/Group";
 import { embedsToMarkers } from "../fnTemplate";
 import { tokensToMarkers } from "../fcTemplate";
 import { controlBytesToMarkers } from "../../types/controlKey";
@@ -112,6 +113,12 @@ export function createFlushField(
 
   const resetFB = () => resetFieldBlockDefaults(s.defaults);
 
+  // ^FO/^FT z rides onto the leaf like the graphics handlers do; L is implicit.
+  const pushLeaf = (o: LabelObject) => {
+    if (s.field.justify === "R") o.fieldJustify = "R";
+    objects.push(o);
+  };
+
   const flushField = () => {
     if (!s.field.fieldType || s.field.pendingFD === null) {
       // Bare `^FN<n>^FD<default>^FS`: Variable declaration, not a field.
@@ -234,7 +241,7 @@ export function createFlushField(
         if (s.field.fpCharGap > 0) {
           textProps.fpCharGap = s.field.fpCharGap;
         }
-        objects.push(
+        pushLeaf(
           makeObj("text", modelPos.x, modelPos.y, textProps, posType, comment),
         );
         resetFB();
@@ -243,7 +250,7 @@ export function createFlushField(
       case "code128": {
         // GS1-128 (^BC…,D): store the canonical compact form, not the parens.
         const gs1 = s.field.bcGs1;
-        objects.push(
+        pushLeaf(
           makeObj(
             "code128",
             s.field.x,
@@ -265,7 +272,7 @@ export function createFlushField(
         break;
       }
       case "code39":
-        objects.push(
+        pushLeaf(
           makeObj(
             "code39",
             s.field.x,
@@ -285,7 +292,7 @@ export function createFlushField(
         );
         break;
       case "ean13":
-        objects.push(
+        pushLeaf(
           makeObj(
             "ean13",
             s.field.x,
@@ -308,7 +315,7 @@ export function createFlushField(
         // content format from toZPL: "{ec}A,{data}"  e.g. "QA,https://example.com"
         const ec = (content[0] ?? "Q") as QrCodeProps["errorCorrection"];
         const data = content.slice(3);
-        objects.push(
+        pushLeaf(
           makeObj(
             "qrcode",
             s.field.x,
@@ -333,7 +340,7 @@ export function createFlushField(
         // valid only there; otherwise the field data is plain, kept verbatim.
         const esc = s.field.dmQuality === 200 ? s.field.dmEscape : undefined;
         const gs1Content = esc ? dataMatrixFdToGs1Content(content, esc) : null;
-        objects.push(
+        pushLeaf(
           makeObj(
             "datamatrix",
             s.field.x,
@@ -355,7 +362,7 @@ export function createFlushField(
         break;
       }
       case "upce":
-        objects.push(
+        pushLeaf(
           makeObj(
             "upce",
             s.field.x,
@@ -390,7 +397,7 @@ export function createFlushField(
       case "planet":
       case "postal":
       case "upcEanExtension":
-        objects.push(
+        pushLeaf(
           makeObj(
             s.field.fieldType,
             s.field.x,
@@ -410,7 +417,7 @@ export function createFlushField(
         );
         break;
       case "gs1databar":
-        objects.push(
+        pushLeaf(
           makeObj(
             "gs1databar",
             s.field.x,
@@ -431,7 +438,7 @@ export function createFlushField(
         );
         break;
       case "pdf417":
-        objects.push(
+        pushLeaf(
           makeObj(
             "pdf417",
             s.field.x,
@@ -450,7 +457,7 @@ export function createFlushField(
         );
         break;
       case "code49":
-        objects.push(
+        pushLeaf(
           makeObj(
             "code49",
             s.field.x,
@@ -469,7 +476,7 @@ export function createFlushField(
         );
         break;
       case "aztec":
-        objects.push(
+        pushLeaf(
           makeObj(
             "aztec",
             s.field.x,
@@ -486,7 +493,7 @@ export function createFlushField(
         );
         break;
       case "maxicode":
-        objects.push(
+        pushLeaf(
           makeObj(
             "maxicode",
             s.field.x,
@@ -501,7 +508,7 @@ export function createFlushField(
         );
         break;
       case "micropdf417":
-        objects.push(
+        pushLeaf(
           makeObj(
             "micropdf417",
             s.field.x,
@@ -519,7 +526,7 @@ export function createFlushField(
         );
         break;
       case "codablock":
-        objects.push(
+        pushLeaf(
           makeObj(
             "codablock",
             s.field.x,
@@ -538,7 +545,7 @@ export function createFlushField(
         );
         break;
       case "tlc39":
-        objects.push(
+        pushLeaf(
           makeObj(
             "tlc39",
             s.field.x,
@@ -562,7 +569,7 @@ export function createFlushField(
         // import still produces a sensible visible object.
         const raw = content.trim().charAt(0).toUpperCase();
         const code = (GS_SYMBOL_CODES.has(raw) ? raw : DEFAULT_GS_SYMBOL) as SymbolProps["symbol"];
-        objects.push(
+        pushLeaf(
           makeObj(
             "symbol",
             s.field.x,
diff --git a/packages/core/src/lib/zplParser/handlers/fields.ts b/packages/core/src/lib/zplParser/handlers/fields.ts
index 24248fd9..7c66513e 100644
--- a/packages/core/src/lib/zplParser/handlers/fields.ts
+++ b/packages/core/src/lib/zplParser/handlers/fields.ts
@@ -10,7 +10,7 @@ import {
   resetFieldBlockDefaults,
   type ParserState,
 } from "../context";
-import { ciToEncoding, dotsFor, getDecoder, int, readRotation } from "../helpers";
+import { ciToEncoding, dotsFor, getDecoder, int, readJustify, readRotation } from "../helpers";
 import type { Handler, Wildcard } from "../types";
 
 /** flushField + appendComment are shared with the orchestrator. */
@@ -78,16 +78,14 @@ export function createFieldHandlers(
       flushField();
       s.field.x = dots(p[0]) + s.label.lhX;
       s.field.y = dots(p[1]) + s.label.lhY + s.label.ltY;
-      // 3rd param z = justification (0 left, 1 right, 2 auto). Only graphics
-      // honour it (right corner); other fields keep the left default for now.
-      s.field.justify = p[2]?.trim() === "1" ? "R" : "L";
+      s.field.justify = readJustify(p[2], s.defaults.fwJustify);
       s.field.positionIsFT = false;
     },
     FT(p) {
       flushField();
       s.field.x = dots(p[0]) + s.label.lhX;
       s.field.y = dots(p[1]) + s.label.lhY + s.label.ltY;
-      s.field.justify = p[2]?.trim() === "1" ? "R" : "L";
+      s.field.justify = readJustify(p[2], s.defaults.fwJustify);
       s.field.positionIsFT = true;
     },
 
@@ -122,13 +120,17 @@ export function createFieldHandlers(
       }
     },
 
-    // ── Field-wide default rotation ───────────────────────────────────────
-    // ^FW{rotation}  e.g. ^FWR
-    FW(_, rest) {
+    // ── Field-wide defaults ───────────────────────────────────────────────
+    // ^FW{rotation},{z}  e.g. ^FWR or ^FWN,1
+    FW(p, rest) {
       const fw = (rest[0] ?? "N").toUpperCase();
       if (fw === "N" || fw === "R" || fw === "I" || fw === "B") {
         s.defaults.fwRotation = fw;
       }
+      // z sets the default justification for ^FO/^FT that omit their own z;
+      // 2 (auto) resets to L, same collapse readJustify applies per field.
+      const z = p[1]?.trim();
+      if (z === "0" || z === "1" || z === "2") s.defaults.fwJustify = z === "1" ? "R" : "L";
     },
 
     // ── Field block ───────────────────────────────────────────────────────
@@ -185,6 +187,9 @@ export function createFieldHandlers(
       s.field.fpDirection = "H";
       s.field.fpCharGap = 0;
       s.field.gsMagnification = undefined;
+      // Spec: an omitted z falls back to ^FW, never to the PRIOR field's z, so
+      // a position-command-less follow field must not inherit the leaked R.
+      s.field.justify = s.defaults.fwJustify;
       resetFieldBlockDefaults(s.defaults);
       s.comment.fnNumber = null;
       s.comment.fnComment = undefined;
diff --git a/packages/core/src/lib/zplParser/helpers.ts b/packages/core/src/lib/zplParser/helpers.ts
index 432b53cf..96d0e81d 100644
--- a/packages/core/src/lib/zplParser/helpers.ts
+++ b/packages/core/src/lib/zplParser/helpers.ts
@@ -10,6 +10,15 @@ export function readRotation(
   return raw && isZplRotation(raw) ? raw : fallback;
 }
 
+/** ^FO/^FT z-justification: explicit 0/1 wins, an omitted z falls back to the
+ *  ^FW default (spec p.201/205); 2 (auto) has no fixed geometry, treated as L. */
+export function readJustify(raw: string | undefined, fallback: "L" | "R"): "L" | "R" {
+  const z = raw?.trim();
+  if (z === "1") return "R";
+  if (z === "0" || z === "2") return "L";
+  return fallback;
+}
+
 /** Validate ^GB/^GC/^GD/^GE colour char; default "B" per spec. */
 export function readColor(raw: string | undefined): "B" | "W" {
   return raw === "W" ? "W" : "B";
diff --git a/packages/core/src/registry/aztec.ts b/packages/core/src/registry/aztec.ts
index 18dd3bf4..dcdf796f 100644
--- a/packages/core/src/registry/aztec.ts
+++ b/packages/core/src/registry/aztec.ts
@@ -1,5 +1,5 @@
 import type { ObjectTypeCore } from "../types/ObjectType";
-import { fieldPos, fdFieldFor } from "./zplHelpers";
+import { fieldPosZ, fdFieldFor } from "./zplHelpers";
 import { moduleTooSmallPreflight } from "../lib/barcodeScannability";
 import { type ZplRotation } from "./rotation";
 
@@ -47,7 +47,7 @@ export const aztec: ObjectTypeCore<AztecProps> = {
     // menuSymbol, numberOfSymbols, structuredID. ecLevel=0 is Zebra's
     // documented default for errorControl, so emitting it as-is is valid.
     return [
-      fieldPos(obj),
+      fieldPosZ(obj),
       `^B0${p.rotation},${p.magnification},N,${p.ecLevel}`,
       fdFieldFor(p.content, ctx, undefined, undefined, CONTROL_CHARS),
     ].join("");
diff --git a/packages/core/src/registry/codablock.ts b/packages/core/src/registry/codablock.ts
index 614ebb04..33351f2c 100644
--- a/packages/core/src/registry/codablock.ts
+++ b/packages/core/src/registry/codablock.ts
@@ -1,5 +1,5 @@
 import type { ObjectTypeCore } from "../types/ObjectType";
-import { fieldPos, fdFieldFor } from "./zplHelpers";
+import { fieldPosZ, fdFieldFor } from "./zplHelpers";
 import { clamp, commitStacked2DTransform } from "./transformHelpers";
 import { moduleTooSmallPreflight } from "../lib/barcodeScannability";
 import { type ZplRotation } from "./rotation";
@@ -67,7 +67,7 @@ export const codablock: ObjectTypeCore<CodablockProps> = {
     // stack, verified on a ZD230). Mode F (Code 128) matches the codablockf preview.
     return [
       `^BY${p.moduleWidth}`,
-      fieldPos(obj),
+      fieldPosZ(obj),
       `^BB${p.rotation},${p.rowHeight},${p.securityLevel},${clampCodablockColumns(p.columns)},,F`,
       fdFieldFor(p.content, ctx),
     ]
diff --git a/packages/core/src/registry/datamatrix.ts b/packages/core/src/registry/datamatrix.ts
index f0a5da36..65e703bf 100644
--- a/packages/core/src/registry/datamatrix.ts
+++ b/packages/core/src/registry/datamatrix.ts
@@ -1,5 +1,5 @@
 import type { ObjectTypeCore } from '../types/ObjectType';
-import { fieldPos, fdFieldFor } from './zplHelpers';
+import { fieldPosZ, fdFieldFor } from './zplHelpers';
 import { DATAMATRIX_FD_ESCAPE, gs1ContentToDataMatrixFd } from '../lib/dataMatrixFd';
 import { moduleTooSmallPreflight } from '../lib/barcodeScannability';
 import { type ZplRotation } from './rotation';
@@ -89,7 +89,7 @@ export const datamatrix: ObjectTypeCore<DataMatrixProps> = {
     ];
     while (params.at(-1) === '') params.pop();
     return [
-      fieldPos(obj),
+      fieldPosZ(obj),
       `^BX${params.join(',')}`,
       fdFieldFor(p.content, ctx, p.gs1 ? gs1ContentToDataMatrixFd : undefined, undefined, CONTROL_CHARS && !p.gs1),
     ].join('');
diff --git a/packages/core/src/registry/index.ts b/packages/core/src/registry/index.ts
index 5285c6b8..58ff9100 100644
--- a/packages/core/src/registry/index.ts
+++ b/packages/core/src/registry/index.ts
@@ -109,6 +109,13 @@ export const STACKED_2D_TYPES: ReadonlySet<string> = new Set(
   (Object.keys(ObjectRegistry) as LeafType[]).filter((t) => ObjectRegistry[t].barcodeClass === 'stacked2d'),
 );
 
+/** True when this type's emitter serializes fieldJustify (graphicAnchor for
+ *  graphics, the z echo in fieldPosZ/textFieldPos for the rest). Only 1D holds
+ *  it un-emitted until the S3 z-emit; dirty tracking reads the same fact. */
+export function emitsFieldJustify(type: string): boolean {
+  return !BARCODE_1D_TYPES.has(type);
+}
+
 /** Dynamic lookup for `LabelObject['type']`; undefined for non-leaf (e.g. `'group'`). */
 export function getEntry(type: string): (typeof ObjectRegistry)[LeafType] | undefined {
   return (ObjectRegistry as Record<string, (typeof ObjectRegistry)[LeafType] | undefined>)[type];
diff --git a/packages/core/src/registry/maxicode.ts b/packages/core/src/registry/maxicode.ts
index 98b830ca..0533aa23 100644
--- a/packages/core/src/registry/maxicode.ts
+++ b/packages/core/src/registry/maxicode.ts
@@ -1,5 +1,5 @@
 import type { ObjectTypeCore } from "../types/ObjectType";
-import { fieldPos, fdFieldFor } from "./zplHelpers";
+import { fieldPosZ, fdFieldFor } from "./zplHelpers";
 
 // ISO/IEC 16023 fixed physical size (28.14 x 26.91 mm); no magnification.
 // 2=US SCM, 3=intl SCM, 4=standard, 5=full EEC, 6=reader programming.
@@ -34,7 +34,7 @@ export const maxicode: ObjectTypeCore<MaxicodeProps> = {
     const p = obj.props;
     // ^BV; structured-append slots fixed at (1,1) since unexposed.
     return [
-      fieldPos(obj),
+      fieldPosZ(obj),
       `^BVN,${p.mode},1,1`,
       fdFieldFor(p.content, ctx),
     ].join("");
diff --git a/packages/core/src/registry/micropdf417.ts b/packages/core/src/registry/micropdf417.ts
index cbca8b4d..0283b0d9 100644
--- a/packages/core/src/registry/micropdf417.ts
+++ b/packages/core/src/registry/micropdf417.ts
@@ -1,5 +1,5 @@
 import type { ObjectTypeCore } from "../types/ObjectType";
-import { fieldPos, fdFieldFor } from "./zplHelpers";
+import { fieldPosZ, fdFieldFor } from "./zplHelpers";
 import { commitStacked2DTransform } from "./transformHelpers";
 import { moduleTooSmallPreflight } from "../lib/barcodeScannability";
 import { type ZplRotation } from "./rotation";
@@ -42,7 +42,7 @@ export const micropdf417: ObjectTypeCore<MicroPdf417Props> = {
     // ^BF{orientation},{rowHeight},{mode}
     return [
       `^BY${p.moduleWidth}`,
-      fieldPos(obj),
+      fieldPosZ(obj),
       `^BF${p.rotation},${p.rowHeight},${p.mode}`,
       fdFieldFor(p.content, ctx, undefined, undefined, CONTROL_CHARS),
     ]
diff --git a/packages/core/src/registry/pdf417.ts b/packages/core/src/registry/pdf417.ts
index 3210c557..42596725 100644
--- a/packages/core/src/registry/pdf417.ts
+++ b/packages/core/src/registry/pdf417.ts
@@ -1,5 +1,5 @@
 import type { ObjectTypeCore } from "../types/ObjectType";
-import { fieldPos, fdFieldFor } from "./zplHelpers";
+import { fieldPosZ, fdFieldFor } from "./zplHelpers";
 import { commitStacked2DTransform } from "./transformHelpers";
 import { moduleTooSmallPreflight } from "../lib/barcodeScannability";
 import { type ZplRotation } from "./rotation";
@@ -46,7 +46,7 @@ export const pdf417: ObjectTypeCore<Pdf417Props> = {
     const p = obj.props;
     return [
       `^BY${p.moduleWidth}`,
-      fieldPos(obj),
+      fieldPosZ(obj),
       `^B7${p.rotation},${p.rowHeight},${p.securityLevel},${p.columns},,,`,
       fdFieldFor(p.content, ctx, undefined, undefined, CONTROL_CHARS),
     ]
diff --git a/packages/core/src/registry/qrcode.ts b/packages/core/src/registry/qrcode.ts
index da2398a4..d0b5b51d 100644
--- a/packages/core/src/registry/qrcode.ts
+++ b/packages/core/src/registry/qrcode.ts
@@ -1,6 +1,6 @@
 import type { ObjectTypeCore } from '../types/ObjectType';
 import type { LabelObjectBase } from '../types/LabelObject';
-import { fieldPos, fdFieldFor } from './zplHelpers';
+import { fieldPosZ, fdFieldFor } from './zplHelpers';
 import { moduleTooSmallPreflight } from '../lib/barcodeScannability';
 import { hasTemplateMarkers } from '../lib/fnTemplate';
 import { formatQrSidecarComment, qrRotatedGfaCached } from '../lib/qrGraphic';
@@ -81,14 +81,14 @@ export const qrcode: ObjectTypeCore<QrCodeProps> = {
       );
       const g = resolved ? qrRotatedGfaCached(p, { ...p, content: resolved }) : null;
       if (g) {
-        return [formatQrSidecarComment(p), fieldPos(obj), g.gfa, '^FS'].join('');
+        return [formatQrSidecarComment(p), fieldPosZ(obj), g.gfa, '^FS'].join('');
       }
     }
     // Prefix passed as the fdFieldFor transform (not baked into content) so it
     // composes with the binding: single-bind default / template / CSV override
     // all get the prefix instead of the payload being emitted raw.
     return [
-      fieldPos(obj),
+      fieldPosZ(obj),
       `^BQN,${p.model},${p.magnification}`,
       fdFieldFor(p.content, ctx, qrFdTransform(obj), undefined, CONTROL_CHARS),
     ].join('');
diff --git a/packages/core/src/registry/symbol.ts b/packages/core/src/registry/symbol.ts
index b7b5cc31..2abd507a 100644
--- a/packages/core/src/registry/symbol.ts
+++ b/packages/core/src/registry/symbol.ts
@@ -1,5 +1,5 @@
 import type { ObjectTypeCore } from '../types/ObjectType';
-import { fieldPos } from './zplHelpers';
+import { fieldPosZ } from './zplHelpers';
 import { commitRotatedWidthHeightTransform } from './transformHelpers';
 import type { ZplRotation } from './rotation';
 
@@ -60,7 +60,7 @@ export const symbol: ObjectTypeCore<SymbolProps> = {
 
   toZPL: (obj) => {
     const p = obj.props;
-    return `${fieldPos(obj)}^GS${p.rotation},${p.height},${p.width}^FD${p.symbol}^FS`;
+    return `${fieldPosZ(obj)}^GS${p.rotation},${p.height},${p.width}^FD${p.symbol}^FS`;
   },
 
   commitTransform: commitRotatedWidthHeightTransform,
diff --git a/packages/core/src/registry/tlc39.ts b/packages/core/src/registry/tlc39.ts
index af90aa79..f816af0f 100644
--- a/packages/core/src/registry/tlc39.ts
+++ b/packages/core/src/registry/tlc39.ts
@@ -1,5 +1,5 @@
 import type { ObjectTypeCore } from "../types/ObjectType";
-import { fieldPos, fdFieldFor } from "./zplHelpers";
+import { fieldPosZ, fdFieldFor } from "./zplHelpers";
 import { commitBarcodeWidthHeightTransform } from "./transformHelpers";
 import { limitedSupportPreflight } from "../lib/barcodeScannability";
 import { type ZplRotation } from "./rotation";
@@ -47,7 +47,7 @@ export const tlc39: ObjectTypeCore<Tlc39Props> = {
     const p = obj.props;
     return [
       `^BY${p.moduleWidth}`,
-      fieldPos(obj),
+      fieldPosZ(obj),
       // r1 (wide:narrow ratio) is not exposed as a prop; emit the
       // canonical "2" so the field round-trips.
       `^BT${p.rotation},${p.moduleWidth},2,${p.height},${p.microPdfRowHeight},${p.microPdfRows}`,
diff --git a/packages/core/src/registry/zplHelpers.ts b/packages/core/src/registry/zplHelpers.ts
index 2483dbfe..321dc148 100644
--- a/packages/core/src/registry/zplHelpers.ts
+++ b/packages/core/src/registry/zplHelpers.ts
@@ -9,12 +9,21 @@ import { getTextRenderMetrics } from "../lib/labelGeometry/textRenderMetrics";
 import { blockInterLineExtentDots } from "../lib/zebraTextLayout";
 import type { LabelObject } from "../types/Group";
 
-/** Emit `^FT` or `^FO` depending on how the object was originally positioned. */
+/** Emit `^FT` or `^FO` depending on how the object was originally positioned.
+ *  1D emitters use this z-less form: their x is import-normalised top-left,
+ *  and z-emit for 1D is the S3 stage. */
 export function fieldPos(obj: LabelObjectBase): string {
   const cmd = obj.positionType === "FT" ? "FT" : "FO";
   return `^${cmd}${obj.x},${obj.y}`;
 }
 
+/** {@link fieldPos} with the z echo: import never normalises these fields, so
+ *  x is still the ZPL anchor and echoing z=1 reproduces the source placement. */
+export function fieldPosZ(obj: LabelObjectBase): string {
+  const z = obj.fieldJustify === "R" ? ",1" : "";
+  return `${fieldPos(obj)}${z}`;
+}
+
 /** Graphic leaf types whose ^FO/^FT origin comes from {@link graphicAnchor}
  *  (the footprint top-left under ^FO, a bottom corner under ^FT). For box /
  *  ellipse / image the model x/y already is that top-left; a line's x/y is an
@@ -39,7 +48,7 @@ export function graphicAnchorCoords(
   w: number,
   h: number,
   positionType: LabelObjectBase["positionType"],
-  justify: "L" | "R" | undefined,
+  justify: LabelObjectBase["fieldJustify"],
 ): { x: number; y: number } {
   if (positionType !== "FT") return { x, y };
   return justify === "R" ? { x: x + w, y: y + h } : { x, y: y + h };
@@ -53,7 +62,7 @@ export function graphicAnchor(
   w: number,
   h: number,
   positionType: LabelObjectBase["positionType"],
-  justify: "L" | "R" | undefined,
+  justify: LabelObjectBase["fieldJustify"],
 ): string {
   const a = graphicAnchorCoords(x, y, w, h, positionType, justify);
   if (positionType !== "FT") return `^FO${a.x},${a.y}`;
@@ -147,7 +156,9 @@ export function textZplAnchorCoords(obj: TextLikeObjForFieldPos): {
 /** Converts EM top-left model coord to ZPL anchor (cap-top/baseline). */
 export function textFieldPos(obj: TextLikeObjForFieldPos): string {
   const a = textZplAnchorCoords(obj);
-  return `^${a.cmd}${a.x},${a.y}`;
+  // Same echo contract as fieldPosZ (text is never import-normalised).
+  const z = obj.fieldJustify === "R" ? ",1" : "";
+  return `^${a.cmd}${a.x},${a.y}${z}`;
 }
 
 /** ^FX has no ^FH escape; strip ^/~ to prevent surrounding-command termination. */
diff --git a/packages/core/src/types/LabelObject.ts b/packages/core/src/types/LabelObject.ts
index c1096fce..32b75109 100644
--- a/packages/core/src/types/LabelObject.ts
+++ b/packages/core/src/types/LabelObject.ts
@@ -9,9 +9,10 @@ export const labelObjectBaseSchema = z.object({
   rotation: z.number(),
   /** 'FT' = field typeset (baseline), 'FO' = field origin (top-left). Defaults to 'FO'. */
   positionType: z.enum(['FO', 'FT']).optional(),
-  /** ^FO/^FT z-justification. 'R' (z=1) anchors a graphic at its right corner;
-   *  absent = left (default). Only graphics (^GB) honour it today. */
-  fieldJustify: z.enum(['L', 'R']).optional(),
+  /** ^FO/^FT z-justification (spec p.201/205): 'R' = right edge (z=1), absent
+   *  = left; 'C' is an editor-only centre for 1D barcodes (no ZPL form).
+   *  Graphics emit L/R via graphicAnchor; barcodes carry it un-emitted. */
+  fieldJustify: z.enum(['L', 'C', 'R']).optional(),
   /** Emitted as ^FX before this field in ZPL output. Carries no print output. */
   comment: z.string().optional(),
   /** When true, blocks position/size/prop edits, drag, resize and deletion.
diff --git a/packages/mcp-server/src/server.ts b/packages/mcp-server/src/server.ts
index de709c8a..34e671f0 100644
--- a/packages/mcp-server/src/server.ts
+++ b/packages/mcp-server/src/server.ts
@@ -109,7 +109,9 @@ export function buildServer(options: BuildServerOptions = {}): McpServer {
       description:
         "Parse a raw ZPL stream into an editable design file (one page per ^XA block; " +
         "feed it to export_zpl or open_in_app) plus parser findings, per-object bounds " +
-        "(dots), and bbox overlaps. Size falls back to the caller's hints then 100x50mm.",
+        "(dots), and bbox overlaps. Size falls back to the caller's hints then 100x50mm. " +
+        "Right-justified (^FO/^FT z=1) fields keep their ZPL x here (headless, no " +
+        "measurement); the app import normalises ^FT+R barcodes to top-left.",
       inputSchema: zplInputShape,
     },
     async ({ zpl, dpmm, widthMm, heightMm }) => json(importZpl(zpl, dpmm, widthMm, heightMm)),
diff --git a/packages/mcp-server/src/tools.ts b/packages/mcp-server/src/tools.ts
index a63c9d57..4c88716a 100644
--- a/packages/mcp-server/src/tools.ts
+++ b/packages/mcp-server/src/tools.ts
@@ -27,7 +27,7 @@ export const objectInputSchema = z.object({
   // Anchor semantics: FO = top-left origin, FT = typeset baseline; fieldJustify
   // right-aligns. Omitted keeps the model default (FO / left).
   positionType: z.enum(["FO", "FT"]).optional(),
-  fieldJustify: z.enum(["L", "R"]).optional(),
+  fieldJustify: z.enum(["L", "C", "R"]).optional(),
   props: z.record(z.string(), z.unknown()).optional(),
 });
 export type ObjectInput = z.infer<typeof objectInputSchema>;
@@ -129,6 +129,12 @@ function parseEnvelope(designFile: unknown): { ok: true; value: DesignFile } | T
  *  defaults; the schema is tolerant, so createDraft guards it up front. */
 function toLabelObject(input: ObjectInput, id: string): LabelObject {
   const defaults = getEntry(input.type)?.defaultProps ?? {};
+  // 'C' has meaning only on 1D barcodes (editor centre); anywhere else it
+  // would persist as dead metadata, so canonicalize it away here.
+  const justify =
+    input.fieldJustify === "C" && getEntry(input.type)?.barcodeClass !== "1d"
+      ? undefined
+      : input.fieldJustify;
   return {
     id,
     type: input.type,
@@ -136,7 +142,7 @@ function toLabelObject(input: ObjectInput, id: string): LabelObject {
     y: input.y,
     rotation: 0,
     ...(input.positionType !== undefined ? { positionType: input.positionType } : {}),
-    ...(input.fieldJustify !== undefined ? { fieldJustify: input.fieldJustify } : {}),
+    ...(justify !== undefined ? { fieldJustify: justify } : {}),
     props: { ...defaults, ...(input.props ?? {}) },
     // Schema is intentionally loose; createDraft rejects unknown types up front.
   } as LabelObject;
@@ -595,7 +601,7 @@ const SCHEMA: SchemaResult = {
     x: "number, dots from left",
     y: "number, dots from top",
     positionType: "optional FO (top-left origin, default) | FT (typeset baseline)",
-    fieldJustify: "optional L (default) | R (right-align)",
+    fieldJustify: "optional L (default) | R | C (centre; 1D barcodes only, dropped elsewhere). On non-1D fields R means x IS the ZPL right-edge anchor and re-emits as z=1; on 1D barcodes x stays the top-left and the editor re-pins on value changes",
     props: "object, merged over defaultProps",
   },
   types: (Object.keys(ObjectRegistry) as (keyof typeof ObjectRegistry)[]).map((type) => {
diff --git a/src/components/Canvas/LabelCanvas.tsx b/src/components/Canvas/LabelCanvas.tsx
index c6b26aa8..f0271cbb 100644
--- a/src/components/Canvas/LabelCanvas.tsx
+++ b/src/components/Canvas/LabelCanvas.tsx
@@ -30,6 +30,10 @@ import { barcodeEncodeFindings } from "./barcodePreflight";
 import { usePreviewBinding } from "../../store/usePreviewBinding";
 import { useContextMenu } from "../../hooks/useContextMenu";
 import { rotateSelectionChanges } from "../../lib/groupRotation";
+import { registerBarcodeWidthProber, unregisterBarcodeWidthProber } from "../../store/anchorRepin";
+import { applyBindingToObject } from "@zplab/core/lib/variableBinding";
+import { objectResolvesCtrl } from "@zplab/core/registry";
+import { measureBarcodeFootprintDots } from "./bwipHelpers";
 import { selectTidyTargets } from "../../lib/tidyClassify";
 import { safeAreaRectDots } from "../../lib/safeArea";
 import { measuredBoundsMap, subscribeMeasuredBounds, getMeasuredSnapshot } from "./measuredBoundsCache";
@@ -451,6 +455,18 @@ export const LabelCanvas = forwardRef<LabelCanvasHandle, Props>(function LabelCa
   } = useCanvasPanZoom({ zoom, onZoomChange, fitZoom, containerRef });
 
   const scale = SCREEN_PX_PER_MM * zoom;
+  // The probe measures the same binding-resolved content KonvaObject draws.
+  const dataRenderMode = useLabelStore((s) => s.canvasSettings.dataRenderMode);
+  useEffect(() => {
+    const { variables: vars, active, clock } = previewBinding;
+    const probe = (o: LabelObject) => {
+      if (isGroup(o)) return null;
+      const resolved = applyBindingToObject(o, vars, active, dataRenderMode, clock, objectResolvesCtrl(o));
+      return measureBarcodeFootprintDots(resolved as LeafObject, scale, label.dpmm);
+    };
+    registerBarcodeWidthProber(probe);
+    return () => unregisterBarcodeWidthProber(probe);
+  }, [scale, label.dpmm, previewBinding, dataRenderMode]);
   const labelWidthPx = effectiveWidthMm * scale;
   const physicalWidthPx = label.widthMm * scale;
   const labelHeightPx = label.heightMm * scale;
diff --git a/src/components/Canvas/bwipHelpers.ts b/src/components/Canvas/bwipHelpers.ts
index d2e3fa70..d8e05260 100644
--- a/src/components/Canvas/bwipHelpers.ts
+++ b/src/components/Canvas/bwipHelpers.ts
@@ -10,7 +10,8 @@ import { upceData6FromFd } from "@zplab/core/registry/hriFormatters";
 import type { LabelObject } from "@zplab/core/types/Group";
 import type { Gs1DatabarProps } from "@zplab/core/registry/gs1databar";
 import { isAxisSwapped, objectRotation } from "@zplab/core/registry/rotation";
-import { dotsToPx } from "@zplab/core/lib/coordinates";
+import { dotsToPx, pxToDots } from "@zplab/core/lib/coordinates";
+import { placeholderContentFor, samplePropsFor } from "../../registry/placeholderContent";
 import {
   GS1_DATABAR_DEFAULT_SEGMENTS,
   GS1_DATABAR_EXPANDED_SYMBOLOGIES,
@@ -641,6 +642,29 @@ export function stateFrameProps(ub: BarcodeDisplaySize["upright"], isEanUpc: boo
     : { width: Math.max(ub.w, 1), height: Math.max(ub.h, 1) };
 }
 
+/** Synchronous footprint probe for the store's anchor re-pin. Blank/uncodable
+ *  content falls back to the sample bars, mirroring BarcodeObject, so prop
+ *  edits on a sample-rendered barcode still re-pin against the drawn width. */
+export function measureBarcodeFootprintDots(
+  obj: LeafObject,
+  scale: number,
+  dpmm: number,
+): { w: number; h: number } | null {
+  const blank = (getObjectStringContent(obj) ?? "").trim() === "";
+  let target = obj;
+  let canvas = blank ? null : renderBarcodeCanvas(obj, scale, dpmm).canvas;
+  if (!canvas) {
+    const sample = placeholderContentFor(obj.type, obj.props);
+    if (!sample) return null;
+    target = { ...obj, props: { ...samplePropsFor(obj.type, obj.props), content: sample } } as LeafObject;
+    canvas = renderBarcodeCanvas(target, scale, dpmm).canvas;
+    if (!canvas) return null;
+  }
+  const dim = getDisplaySize(target, canvas, scale, dpmm);
+  if (dim.w <= 0 || dim.h <= 0) return null;
+  return { w: pxToDots(dim.w, scale, dpmm), h: pxToDots(dim.h, scale, dpmm) };
+}
+
 export function getDisplaySize(
   obj: LeafObject,
   canvas: HTMLCanvasElement,
diff --git a/src/components/Output/ZplImportModal.tsx b/src/components/Output/ZplImportModal.tsx
index 788ae4a8..8135c8bb 100644
--- a/src/components/Output/ZplImportModal.tsx
+++ b/src/components/Output/ZplImportModal.tsx
@@ -2,6 +2,8 @@ import { useRef, useState } from 'react';
 import { XMarkIcon, ClipboardDocumentIcon, CheckIcon, FolderOpenIcon } from '@heroicons/react/16/solid';
 import { importZplText, routeSetupCommands, mergeSetupFonts, type ZplImportResult, type SetupCommandChoice } from '@zplab/core/lib/zplImportService';
 import { readFileAsText } from '../../lib/readFile';
+import { measureBarcodeFootprintDots } from '../Canvas/bwipHelpers';
+import type { LeafObject } from '@zplab/core/registry';
 import { useLabelStore } from '../../store/labelStore';
 import type { Page } from '@zplab/core/types/Group';
 import type { LabelConfig } from '@zplab/core/types/LabelConfig';
@@ -103,7 +105,10 @@ export function ZplImportModal({ onClose }: Props) {
   // Shared by both entry points (paste, file picker); they differ only in how
   // they obtain the text.
   const processImport = (text: string) => {
-    const imported = importZplText(text, label.dpmm);
+    // scale = dpmm renders at 1px per dot: exact, zoom-independent footprints.
+    const imported = importZplText(text, label.dpmm, {
+      measureFootprint: (o) => measureBarcodeFootprintDots(o as LeafObject, label.dpmm, label.dpmm),
+    });
     const { labelConfig, printerProfile, pages } = imported;
     const totalObjects = pages.reduce((s, p) => s + p.objects.length, 0);
     if (
diff --git a/src/components/Properties/PropertiesPanel.tsx b/src/components/Properties/PropertiesPanel.tsx
index ccd4fcba..b9f297c1 100644
--- a/src/components/Properties/PropertiesPanel.tsx
+++ b/src/components/Properties/PropertiesPanel.tsx
@@ -4,7 +4,7 @@ import { useLabelStore, useCurrentObjects, selectPreviewLocksEditor } from "../.
 import type { LabelCanvasHandle } from "../Canvas/LabelCanvas";
 import type { AlignOp, DistributeAxis, AlignRef } from "../../lib/align";
 import type { AlignSelectionRef } from "../../store/slices/uiSlice";
-import { getEntry } from "@zplab/core/registry";
+import { getEntry, BARCODE_1D_TYPES } from "@zplab/core/registry";
 import { getPanel } from "../../registry/panels";
 import { canGroupSelection, findObjectById, hasLockedAncestor, isGroup } from "@zplab/core/types/Group";
 import { symbologyTargets } from "../../lib/symbologySwitch";
@@ -333,6 +333,30 @@ export function PropertiesPanel({ canvasRef }: PropertiesPanelProps) {
               />
             </div>
           )}
+          {/* Origin semantics (which edge x pins), hence the position box. */}
+          {!groupRow && BARCODE_1D_TYPES.has(obj.type) && (
+            <div className="flex items-center justify-between gap-2">
+              <Tooltip content={t.properties.valueAnchorHint}>
+                <span className={labelCls}>{t.properties.valueAnchor}</span>
+              </Tooltip>
+              <SegmentedControl
+                value={obj.fieldJustify ?? "L"}
+                onChange={(v) => {
+                  // L maps back to the implicit default; skip no-op clicks so
+                  // they don't mint phantom undo steps / document diffs.
+                  const fieldJustify = v === "L" ? undefined : v;
+                  if (fieldJustify === obj.fieldJustify) return;
+                  updateObject(obj.id, { fieldJustify });
+                }}
+                options={[
+                  { value: "L", label: t.registry.text.justifyL },
+                  { value: "C", label: t.registry.text.justifyC },
+                  { value: "R", label: t.registry.text.justifyR },
+                ]}
+                aria-label={t.properties.valueAnchor}
+              />
+            </div>
+          )}
           <PositionSectionHeader
             hideHeading
             unitSuffix={!groupRow ? unitLabel(unit) : undefined}
diff --git a/src/lib/fieldJustifyImport.test.ts b/src/lib/fieldJustifyImport.test.ts
new file mode 100644
index 00000000..a9696d79
--- /dev/null
+++ b/src/lib/fieldJustifyImport.test.ts
@@ -0,0 +1,113 @@
+import { describe, it, expect } from "vitest";
+import { importZplText } from "@zplab/core/lib/zplImportService";
+import { generateZPL } from "@zplab/core/lib/zplGenerator";
+import type { LabelObject } from "@zplab/core/types/Group";
+
+const leaf = (zpl: string, opts?: Parameters<typeof importZplText>[2]): LabelObject => {
+  const r = importZplText(zpl, 8, opts);
+  const o = r.pages[0]?.objects[0];
+  expect(o).toBeDefined();
+  return o!;
+};
+
+describe("^FO/^FT z-justification import", () => {
+  it("stamps fieldJustify=R from an explicit z=1 on a barcode", () => {
+    const o = leaf("^XA^FO100,50,1^BCN,100,Y,N,N^FD123^FS^XZ");
+    expect(o.fieldJustify).toBe("R");
+    // No measurer: x stays at the ZPL (right-edge) value.
+    expect(o.x).toBe(100);
+  });
+
+  it("leaves fieldJustify absent without z (left is implicit)", () => {
+    const o = leaf("^XA^FO100,50^BCN,100,Y,N,N^FD123^FS^XZ");
+    expect(o.fieldJustify).toBeUndefined();
+  });
+
+  it("normalises a right-justified ^FT barcode x via the injected measurer", () => {
+    const o = leaf("^XA^FT100,150,1^BCN,100,Y,N,N^FD123^FS^XZ", {
+      measureFootprint: () => ({ w: 40, h: 100 }),
+    });
+    expect(o.x).toBe(60);
+    expect(o.fieldJustify).toBe("R");
+  });
+
+  it("leaves a ROTATED ^FT z=1 barcode unshifted (rotation interaction unverified)", () => {
+    const o = leaf("^XA^FT100,150,1^BCR,100,Y,N,N^FD123^FS^XZ", {
+      measureFootprint: () => ({ w: 40, h: 100 }),
+    });
+    expect(o.x).toBe(100);
+    expect(o.fieldJustify).toBe("R");
+  });
+
+  it("leaves ^FO z=1 x untouched (z effect on ^FO unverified on firmware)", () => {
+    const o = leaf("^XA^FO100,50,1^BCN,100,Y,N,N^FD123^FS^XZ", {
+      measureFootprint: () => ({ w: 40, h: 100 }),
+    });
+    expect(o.x).toBe(100);
+    expect(o.fieldJustify).toBe("R");
+  });
+
+  it("stamps but never shifts text (import-time text measurement unreliable)", () => {
+    const o = leaf("^XA^FO100,50,1^A0N,30,30^FDHi^FS^XZ", {
+      measureFootprint: () => ({ w: 40, h: 30 }),
+    });
+    expect(o.type).toBe("text");
+    expect(o.fieldJustify).toBe("R");
+    expect(o.x).toBe(100);
+  });
+
+  it("^FW z sets the default for fields whose ^FO omits z", () => {
+    const zpl = "^XA^FWN,1^FO100,50^BCN,100,Y,N,N^FD123^FS^FO300,50,0^BCN,100,Y,N,N^FD456^FS^XZ";
+    const r = importZplText(zpl, 8);
+    const [a, b] = r.pages[0]!.objects;
+    // Omitted z inherits the ^FW default; explicit z=0 overrides it.
+    expect(a!.fieldJustify).toBe("R");
+    expect(b!.fieldJustify).toBeUndefined();
+  });
+
+  it("^FT carries z the same way", () => {
+    const o = leaf("^XA^FT100,150,1^BCN,100,Y,N,N^FD123^FS^XZ");
+    expect(o.positionType).toBe("FT");
+    expect(o.fieldJustify).toBe("R");
+  });
+
+  it("a position-less follow field falls back to the ^FW default, not the prior z", () => {
+    const r = importZplText("^XA^FO100,50,1^A0N,30,30^FDa^FS^A0N,30,30^FDb^FS^XZ", 8);
+    expect(r.pages[0]!.objects[1]!.fieldJustify).toBeUndefined();
+  });
+
+  it("^FW z=2 (auto) resets an earlier R default to left", () => {
+    const zpl = "^XA^FWN,1^FWN,2^FO100,50^BCN,100,Y,N,N^FD123^FS^XZ";
+    expect(importZplText(zpl, 8).pages[0]!.objects[0]!.fieldJustify).toBeUndefined();
+  });
+
+  it("a later page's position-less first field inherits the persisted ^FW default", () => {
+    const zpl = "^XA^FWN,1^A0N,30,30^FDa^FS^XZ^XA^A0N,30,30^FDb^FS^XZ";
+    const r = importZplText(zpl, 8);
+    expect(r.pages[1]!.objects[0]!.fieldJustify).toBe("R");
+  });
+
+  it("echoes z=1 on re-emit for un-normalised text and 2D fields", () => {
+    // Un-normalised fields keep their anchor x; the echo restores the
+    // original placement byte-true.
+    const text = importZplText("^XA^FO100,50,1^A0N,30,30^FDHi^FS^XZ", 8);
+    const textZpl = generateZPL({ widthMm: 100, heightMm: 50, dpmm: 8 }, text.pages[0]!.objects);
+    expect(textZpl).toMatch(/\^FO\d+,\d+,1/);
+    const qr = importZplText("^XA^FT100,150,1^BQN,2,4^FDQA,HELLO^FS^XZ", 8);
+    const qrZpl = generateZPL({ widthMm: 100, heightMm: 50, dpmm: 8 }, qr.pages[0]!.objects);
+    expect(qrZpl).toContain("^FT100,150,1");
+  });
+
+  it("S3 tripwire: a right-justified 1D barcode emits ^FO without a z-param", () => {
+    // When barcode z-emit lands this goes red; the dirty-tracking
+    // emitsFieldJustify predicate must flip together with the emitter.
+    const o = {
+      id: "b1", type: "code128", x: 60, y: 50, rotation: 0, fieldJustify: "R",
+      props: { content: "123", height: 100, moduleWidth: 2, rotation: "N",
+               printInterpretation: false, checkDigit: false },
+    } as unknown as LabelObject;
+    const zpl = generateZPL({ widthMm: 100, heightMm: 50, dpmm: 8 }, [o]);
+    expect(zpl).toContain("^FO60,50^");
+    expect(zpl).not.toContain("^FO60,50,1");
+  });
+});
diff --git a/src/lib/symbologySwitch.test.ts b/src/lib/symbologySwitch.test.ts
index bc270cd3..45064865 100644
--- a/src/lib/symbologySwitch.test.ts
+++ b/src/lib/symbologySwitch.test.ts
@@ -164,6 +164,13 @@ describe('convertSymbologyMapper', () => {
     expect(c39.moduleWidth).toBe(2);
   });
 
+  it('carries fieldJustify within the 1D class, drops it across the boundary', () => {
+    const src = { ...barcode('code128', { content: 'A' }), fieldJustify: 'R' } as LabelObject;
+    expect(convertSymbologyMapper('code39' as never)(src).fieldJustify).toBe('R');
+    // Crossing the class boundary would break the echo invariant (mapper).
+    expect(convertSymbologyMapper('qrcode' as never)(src).fieldJustify).toBeUndefined();
+  });
+
   it('is a no-op for same type and non-barcode objects', () => {
     expect(convertSymbologyMapper('code128' as never)(source)).toBe(source);
     const text = barcode('text', { content: 'hi' });
diff --git a/src/lib/symbologySwitch.ts b/src/lib/symbologySwitch.ts
index 3e1d6e08..04fd56a2 100644
--- a/src/lib/symbologySwitch.ts
+++ b/src/lib/symbologySwitch.ts
@@ -102,6 +102,14 @@ export function convertSymbologyMapper(targetType: LeafType): (obj: LabelObject)
       // The serial-off restore snapshot travels with the serial flag.
       if (typeof p.preSerialContent === "string") props.preSerialContent = p.preSerialContent;
     }
-    return { ...obj, type: targetType, props } as unknown as LabelObject;
+    // x-space differs per class (see fieldPos/fieldPosZ), so the flag must
+    // not survive a 1D <-> non-1D crossing.
+    const crossed = (source.barcodeClass === '1d') !== (target.barcodeClass === '1d');
+    return {
+      ...obj,
+      type: targetType,
+      props,
+      ...(crossed ? { fieldJustify: undefined } : {}),
+    } as unknown as LabelObject;
   };
 }
diff --git a/src/locales/ar.ts b/src/locales/ar.ts
index 096680a8..971aa486 100644
--- a/src/locales/ar.ts
+++ b/src/locales/ar.ts
@@ -346,6 +346,8 @@ const ar = {
     optionsSection: 'خيارات',
     contentSection: 'المحتوى',
     settingsSection: 'الإعدادات',
+    valueAnchor: 'مرساة',
+    valueAnchorHint: 'الحافة التي تبقى ثابتة عند تغيّر العرض بسبب تغيير القيمة',
     typographySection: 'الطباعة',
     name: 'الاسم',
     x: 'X',
diff --git a/src/locales/bg.ts b/src/locales/bg.ts
index 258923fb..33d3b6c8 100644
--- a/src/locales/bg.ts
+++ b/src/locales/bg.ts
@@ -346,6 +346,8 @@ const bg = {
     optionsSection: 'Опции',
     contentSection: 'Съдържание',
     settingsSection: 'Настройки',
+    valueAnchor: 'Котва',
+    valueAnchorHint: 'Ръб, който остава фиксиран, когато промяна на стойността променя ширината',
     typographySection: 'Типография',
     name: 'Име',
     x: 'X',
diff --git a/src/locales/cs.ts b/src/locales/cs.ts
index 82975583..32c4c07c 100644
--- a/src/locales/cs.ts
+++ b/src/locales/cs.ts
@@ -346,6 +346,8 @@ const cs = {
     optionsSection: 'Možnosti',
     contentSection: 'Obsah',
     settingsSection: 'Nastavení',
+    valueAnchor: 'Kotva',
+    valueAnchorHint: 'Hrana, která zůstává pevná, když změna hodnoty změní šířku',
     typographySection: 'Typografie',
     name: 'Název',
     x: 'X',
diff --git a/src/locales/da.ts b/src/locales/da.ts
index 874c3e28..287aecdc 100644
--- a/src/locales/da.ts
+++ b/src/locales/da.ts
@@ -346,6 +346,8 @@ const da = {
     optionsSection: 'Valg',
     contentSection: 'Indhold',
     settingsSection: 'Indstillinger',
+    valueAnchor: 'Anker',
+    valueAnchorHint: 'Kanten der forbliver fast, når en værdiændring ændrer bredden',
     typographySection: 'Typografi',
     name: 'Navn',
     x: 'X',
diff --git a/src/locales/de.ts b/src/locales/de.ts
index 2611fab6..ebb4fff9 100644
--- a/src/locales/de.ts
+++ b/src/locales/de.ts
@@ -346,6 +346,8 @@ const de = {
     optionsSection: 'Optionen',
     contentSection: 'Inhalt',
     settingsSection: 'Einstellungen',
+    valueAnchor: 'Anker',
+    valueAnchorHint: 'Kante, die beim Ändern der Breite durch eine Wertänderung fix bleibt',
     typographySection: 'Typografie',
     name: 'Name',
     x: 'X',
diff --git a/src/locales/el.ts b/src/locales/el.ts
index 7fdfe320..2d252cc8 100644
--- a/src/locales/el.ts
+++ b/src/locales/el.ts
@@ -346,6 +346,8 @@ const el = {
     optionsSection: 'Επιλογές',
     contentSection: 'Περιεχόμενο',
     settingsSection: 'Ρυθμίσεις',
+    valueAnchor: 'Άγκυρα',
+    valueAnchorHint: 'Η άκρη που παραμένει σταθερή όταν μια αλλαγή τιμής μεταβάλλει το πλάτος',
     typographySection: 'Τυπογραφία',
     name: 'Όνομα',
     x: 'X',
diff --git a/src/locales/en.ts b/src/locales/en.ts
index 4817416c..0e9737d9 100644
--- a/src/locales/en.ts
+++ b/src/locales/en.ts
@@ -346,6 +346,8 @@ const en = {
     optionsSection: 'Options',
     contentSection: 'Content',
     settingsSection: 'Settings',
+    valueAnchor: 'Anchor',
+    valueAnchorHint: 'Edge that stays fixed when a value change alters the width',
     typographySection: 'Typography',
     name: 'Name',
     x: 'X',
diff --git a/src/locales/es.ts b/src/locales/es.ts
index 4c4210a6..4be4a6cc 100644
--- a/src/locales/es.ts
+++ b/src/locales/es.ts
@@ -346,6 +346,8 @@ const es = {
     optionsSection: 'Opciones',
     contentSection: 'Contenido',
     settingsSection: 'Ajustes',
+    valueAnchor: 'Anclaje',
+    valueAnchorHint: 'Borde que permanece fijo cuando un cambio de valor altera el ancho',
     typographySection: 'Tipografía',
     name: 'Nombre',
     x: 'X',
diff --git a/src/locales/et.ts b/src/locales/et.ts
index f1bf6985..ba960e05 100644
--- a/src/locales/et.ts
+++ b/src/locales/et.ts
@@ -346,6 +346,8 @@ const et = {
     optionsSection: 'Valikud',
     contentSection: 'Sisu',
     settingsSection: 'Sätted',
+    valueAnchor: 'Ankur',
+    valueAnchorHint: 'Serv, mis jääb fikseerituks, kui väärtuse muutus muudab laiust',
     typographySection: 'Tüpograafia',
     name: 'Nimi',
     x: 'X',
diff --git a/src/locales/fa.ts b/src/locales/fa.ts
index ca0b86d8..eb9b3307 100644
--- a/src/locales/fa.ts
+++ b/src/locales/fa.ts
@@ -346,6 +346,8 @@ const fa = {
     optionsSection: 'گزینه‌ها',
     contentSection: 'محتوا',
     settingsSection: 'تنظیمات',
+    valueAnchor: 'لنگر',
+    valueAnchorHint: 'لبه‌ای که هنگام تغییر عرض بر اثر تغییر مقدار ثابت می‌ماند',
     typographySection: 'تایپوگرافی',
     name: 'نام',
     x: 'X',
diff --git a/src/locales/fi.ts b/src/locales/fi.ts
index 3558e3de..aba248fa 100644
--- a/src/locales/fi.ts
+++ b/src/locales/fi.ts
@@ -346,6 +346,8 @@ const fi = {
     optionsSection: 'Valinnat',
     contentSection: 'Sisältö',
     settingsSection: 'Asetukset',
+    valueAnchor: 'Ankkuri',
+    valueAnchorHint: 'Reuna, joka pysyy kiinteänä, kun arvon muutos muuttaa leveyttä',
     typographySection: 'Typografia',
     name: 'Nimi',
     x: 'X',
diff --git a/src/locales/fr.ts b/src/locales/fr.ts
index b7b81b23..20161a2a 100644
--- a/src/locales/fr.ts
+++ b/src/locales/fr.ts
@@ -346,6 +346,8 @@ const fr = {
     optionsSection: 'Options',
     contentSection: 'Contenu',
     settingsSection: 'Paramètres',
+    valueAnchor: 'Ancrage',
+    valueAnchorHint: "Bord qui reste fixe lorsqu'une modification de valeur change la largeur",
     typographySection: 'Typographie',
     name: 'Nom',
     x: 'X',
diff --git a/src/locales/he.ts b/src/locales/he.ts
index a4360e19..4bc0231c 100644
--- a/src/locales/he.ts
+++ b/src/locales/he.ts
@@ -346,6 +346,8 @@ const he = {
     optionsSection: 'אפשרויות',
     contentSection: 'תוכן',
     settingsSection: 'הגדרות',
+    valueAnchor: 'עוגן',
+    valueAnchorHint: 'הקצה שנשאר קבוע כאשר שינוי בערך משנה את הרוחב',
     typographySection: 'טיפוגרפיה',
     name: 'שם',
     x: 'X',
diff --git a/src/locales/hr.ts b/src/locales/hr.ts
index 05da05e6..77d7f466 100644
--- a/src/locales/hr.ts
+++ b/src/locales/hr.ts
@@ -346,6 +346,8 @@ const hr = {
     optionsSection: 'Opcije',
     contentSection: 'Sadržaj',
     settingsSection: 'Postavke',
+    valueAnchor: 'Sidro',
+    valueAnchorHint: 'Rub koji ostaje fiksan kada promjena vrijednosti mijenja širinu',
     typographySection: 'Tipografija',
     name: 'Naziv',
     x: 'X',
diff --git a/src/locales/hu.ts b/src/locales/hu.ts
index f74cd40b..8143764f 100644
--- a/src/locales/hu.ts
+++ b/src/locales/hu.ts
@@ -346,6 +346,8 @@ const hu = {
     optionsSection: 'Lehetőségek',
     contentSection: 'Tartalom',
     settingsSection: 'Beállítások',
+    valueAnchor: 'Horgony',
+    valueAnchorHint: 'Az a szél, amely rögzítve marad, ha egy értékváltozás megváltoztatja a szélességet',
     typographySection: 'Tipográfia',
     name: 'Név',
     x: 'X',
diff --git a/src/locales/it.ts b/src/locales/it.ts
index 3d1877eb..d716e47b 100644
--- a/src/locales/it.ts
+++ b/src/locales/it.ts
@@ -346,6 +346,8 @@ const it = {
     optionsSection: 'Opzioni',
     contentSection: 'Contenuto',
     settingsSection: 'Impostazioni',
+    valueAnchor: 'Ancora',
+    valueAnchorHint: 'Bordo che rimane fisso quando una modifica del valore altera la larghezza',
     typographySection: 'Tipografia',
     name: 'Nome',
     x: 'X',
diff --git a/src/locales/ja.ts b/src/locales/ja.ts
index 5ea4922b..88c4eb34 100644
--- a/src/locales/ja.ts
+++ b/src/locales/ja.ts
@@ -346,6 +346,8 @@ const ja = {
     optionsSection: 'オプション',
     contentSection: 'コンテンツ',
     settingsSection: '設定',
+    valueAnchor: 'アンカー',
+    valueAnchorHint: '値の変更で幅が変わる際に固定されたままの辺',
     typographySection: 'タイポグラフィ',
     name: '名前',
     x: 'X',
diff --git a/src/locales/ko.ts b/src/locales/ko.ts
index 295fd8e6..70cf317d 100644
--- a/src/locales/ko.ts
+++ b/src/locales/ko.ts
@@ -346,6 +346,8 @@ const ko = {
     optionsSection: '옵션',
     contentSection: '콘텐츠',
     settingsSection: '설정',
+    valueAnchor: '앵커',
+    valueAnchorHint: '값 변경으로 너비가 바뀔 때 고정된 상태로 유지되는 모서리',
     typographySection: '타이포그래피',
     name: '이름',
     x: 'X',
diff --git a/src/locales/lt.ts b/src/locales/lt.ts
index e42f92b7..d6e54ee8 100644
--- a/src/locales/lt.ts
+++ b/src/locales/lt.ts
@@ -346,6 +346,8 @@ const lt = {
     optionsSection: 'Parinktys',
     contentSection: 'Turinys',
     settingsSection: 'Nustatymai',
+    valueAnchor: 'Inkaras',
+    valueAnchorHint: 'Kraštas, kuris išlieka fiksuotas, kai reikšmės pakeitimas pakeičia plotį',
     typographySection: 'Tipografija',
     name: 'Pavadinimas',
     x: 'X',
diff --git a/src/locales/lv.ts b/src/locales/lv.ts
index 23d506d4..5d3313e6 100644
--- a/src/locales/lv.ts
+++ b/src/locales/lv.ts
@@ -346,6 +346,8 @@ const lv = {
     optionsSection: 'Opcijas',
     contentSection: 'Saturs',
     settingsSection: 'Iestatījumi',
+    valueAnchor: 'Enkurs',
+    valueAnchorHint: 'Mala, kas paliek fiksēta, kad vērtības izmaiņas maina platumu',
     typographySection: 'Tipogrāfija',
     name: 'Nosaukums',
     x: 'X',
diff --git a/src/locales/nl.ts b/src/locales/nl.ts
index 58b852ef..4ae1e6e7 100644
--- a/src/locales/nl.ts
+++ b/src/locales/nl.ts
@@ -346,6 +346,8 @@ const nl = {
     optionsSection: 'Opties',
     contentSection: 'Inhoud',
     settingsSection: 'Instellingen',
+    valueAnchor: 'Anker',
+    valueAnchorHint: 'Rand die vast blijft wanneer een waardewijziging de breedte verandert',
     typographySection: 'Typografie',
     name: 'Naam',
     x: 'X',
diff --git a/src/locales/no.ts b/src/locales/no.ts
index 2ef2e01c..1a54d90e 100644
--- a/src/locales/no.ts
+++ b/src/locales/no.ts
@@ -346,6 +346,8 @@ const no = {
     optionsSection: 'Alternativer',
     contentSection: 'Innhold',
     settingsSection: 'Innstillinger',
+    valueAnchor: 'Anker',
+    valueAnchorHint: 'Kanten som forblir fast når en verdiendring endrer bredden',
     typographySection: 'Typografi',
     name: 'Navn',
     x: 'X',
diff --git a/src/locales/pl.ts b/src/locales/pl.ts
index f65f8762..dcbdac53 100644
--- a/src/locales/pl.ts
+++ b/src/locales/pl.ts
@@ -346,6 +346,8 @@ const pl = {
     optionsSection: 'Opcje',
     contentSection: 'Treść',
     settingsSection: 'Ustawienia',
+    valueAnchor: 'Kotwica',
+    valueAnchorHint: 'Krawędź, która pozostaje nieruchoma, gdy zmiana wartości zmienia szerokość',
     typographySection: 'Typografia',
     name: 'Nazwa',
     x: 'X',
diff --git a/src/locales/pt.ts b/src/locales/pt.ts
index 6d82195a..60b6e3a4 100644
--- a/src/locales/pt.ts
+++ b/src/locales/pt.ts
@@ -346,6 +346,8 @@ const pt = {
     optionsSection: 'Opções',
     contentSection: 'Conteúdo',
     settingsSection: 'Definições',
+    valueAnchor: 'Âncora',
+    valueAnchorHint: 'Borda que permanece fixa quando uma alteração de valor altera a largura',
     typographySection: 'Tipografia',
     name: 'Nome',
     x: 'X',
diff --git a/src/locales/ro.ts b/src/locales/ro.ts
index 870d0ea2..8b72d93e 100644
--- a/src/locales/ro.ts
+++ b/src/locales/ro.ts
@@ -346,6 +346,8 @@ const ro = {
     optionsSection: 'Opțiuni',
     contentSection: 'Conținut',
     settingsSection: 'Setări',
+    valueAnchor: 'Ancoră',
+    valueAnchorHint: 'Marginea care rămâne fixă atunci când o modificare a valorii schimbă lățimea',
     typographySection: 'Tipografie',
     name: 'Nume',
     x: 'X',
diff --git a/src/locales/sk.ts b/src/locales/sk.ts
index 0ffb8aca..f5dfe690 100644
--- a/src/locales/sk.ts
+++ b/src/locales/sk.ts
@@ -346,6 +346,8 @@ const sk = {
     optionsSection: 'Možnosti',
     contentSection: 'Obsah',
     settingsSection: 'Nastavenia',
+    valueAnchor: 'Kotva',
+    valueAnchorHint: 'Hrana, ktorá zostáva pevná, keď zmena hodnoty zmení šírku',
     typographySection: 'Typografia',
     name: 'Názov',
     x: 'X',
diff --git a/src/locales/sl.ts b/src/locales/sl.ts
index cbef41c3..175b62e1 100644
--- a/src/locales/sl.ts
+++ b/src/locales/sl.ts
@@ -346,6 +346,8 @@ const sl = {
     optionsSection: 'Možnosti',
     contentSection: 'Vsebina',
     settingsSection: 'Nastavitve',
+    valueAnchor: 'Sidro',
+    valueAnchorHint: 'Rob, ki ostane fiksen, ko sprememba vrednosti spremeni širino',
     typographySection: 'Tipografija',
     name: 'Ime',
     x: 'X',
diff --git a/src/locales/sr.ts b/src/locales/sr.ts
index fde3b60c..ee2d686b 100644
--- a/src/locales/sr.ts
+++ b/src/locales/sr.ts
@@ -346,6 +346,8 @@ const sr = {
     optionsSection: 'Опције',
     contentSection: 'Садржај',
     settingsSection: 'Подешавања',
+    valueAnchor: 'Сидро',
+    valueAnchorHint: 'Ивица која остаје фиксна када промена вредности мења ширину',
     typographySection: 'Типографија',
     name: 'Naziv',
     x: 'X',
diff --git a/src/locales/sv.ts b/src/locales/sv.ts
index 187dc796..d58bd6c1 100644
--- a/src/locales/sv.ts
+++ b/src/locales/sv.ts
@@ -346,6 +346,8 @@ const sv = {
     optionsSection: 'Alternativ',
     contentSection: 'Innehåll',
     settingsSection: 'Inställningar',
+    valueAnchor: 'Ankare',
+    valueAnchorHint: 'Kanten som förblir fast när en värdeändring ändrar bredden',
     typographySection: 'Typografi',
     name: 'Namn',
     x: 'X',
diff --git a/src/locales/tr.ts b/src/locales/tr.ts
index 2c99b8b8..d8e0a819 100644
--- a/src/locales/tr.ts
+++ b/src/locales/tr.ts
@@ -346,6 +346,8 @@ const tr = {
     optionsSection: 'Seçenekler',
     contentSection: 'İçerik',
     settingsSection: 'Ayarlar',
+    valueAnchor: 'Çapa',
+    valueAnchorHint: 'Değer değişikliği genişliği değiştirdiğinde sabit kalan kenar',
     typographySection: 'Tipografi',
     name: 'Ad',
     x: 'X',
diff --git a/src/locales/zh-hans.ts b/src/locales/zh-hans.ts
index 4b58f09a..34e16928 100644
--- a/src/locales/zh-hans.ts
+++ b/src/locales/zh-hans.ts
@@ -346,6 +346,8 @@ const zhHans = {
     optionsSection: '选项',
     contentSection: '内容',
     settingsSection: '设置',
+    valueAnchor: '锚点',
+    valueAnchorHint: '数值变化导致宽度改变时保持固定的边',
     typographySection: '排版',
     name: '名称',
     x: 'X',
diff --git a/src/locales/zh-hant.ts b/src/locales/zh-hant.ts
index d8646ebe..a3579a03 100644
--- a/src/locales/zh-hant.ts
+++ b/src/locales/zh-hant.ts
@@ -346,6 +346,8 @@ const zhHant = {
     optionsSection: '選項',
     contentSection: '內容',
     settingsSection: '設定',
+    valueAnchor: '錨點',
+    valueAnchorHint: '數值變化導致寬度改變時保持固定的邊',
     typographySection: '排版',
     name: '名稱',
     x: 'X',
diff --git a/src/store/anchorRepin.test.ts b/src/store/anchorRepin.test.ts
new file mode 100644
index 00000000..db5bdb29
--- /dev/null
+++ b/src/store/anchorRepin.test.ts
@@ -0,0 +1,208 @@
+import { describe, it, expect, afterEach } from "vitest";
+import { applyObjectChanges, NON_EMITTING_PROP_KEYS } from "./labelStore.internals";
+import { registerBarcodeWidthProber, unregisterBarcodeWidthProber, probeBarcodeFootprint, anchorRepin } from "./anchorRepin";
+import { stampDirtyLeaves } from "./dirtyTracking";
+import { convertSymbologyMapper } from "../lib/symbologySwitch";
+import { valueAnchorShift } from "@zplab/core/lib/valueAnchor";
+import type { LabelObject } from "@zplab/core/types/Group";
+
+// Fake probe: width tracks content length, axes swap under R rotation.
+const probe = (o: LabelObject) => {
+  const p = (o as { props: { content: string; rotation?: string } }).props;
+  const w = p.content.length * 10;
+  const swapped = p.rotation === "R" || p.rotation === "B";
+  return swapped ? { w: 30, h: w } : { w, h: 30 };
+};
+
+const barcode = (over: object = {}, props: object = {}): LabelObject =>
+  ({
+    id: "b1",
+    type: "code128",
+    x: 100,
+    y: 50,
+    fieldJustify: "R",
+    props: { content: "AB", height: 100, moduleWidth: 2, rotation: "N", ...props },
+    ...over,
+  }) as unknown as LabelObject;
+
+describe("anchorRepin", () => {
+  afterEach(() => registerBarcodeWidthProber(null));
+
+  it("keeps the right edge fixed when the content widens", () => {
+    registerBarcodeWidthProber(probe);
+    const next = applyObjectChanges(barcode(), { props: { content: "ABCD" } });
+    // Width 20 -> 40: origin moves left by the full delta.
+    expect(next.x).toBe(80);
+    expect(next.y).toBe(50);
+  });
+
+  it("splits an odd delta away from zero for a centre justify", () => {
+    // Odd delta (-7) so a plain Math.round(delta/2) regression turns red.
+    const oddProbe = (o: LabelObject) => {
+      const c = (o as { props: { content: string } }).props.content;
+      return { w: c === "ABCD" ? 27 : 20, h: 30 };
+    };
+    registerBarcodeWidthProber(oddProbe);
+    const next = applyObjectChanges(barcode({ fieldJustify: "C" }), { props: { content: "ABCD" } });
+    expect(next.x).toBe(96);
+  });
+
+  it("does nothing for L/absent justify or a width-neutral edit", () => {
+    registerBarcodeWidthProber(probe);
+    expect(applyObjectChanges(barcode({ fieldJustify: "L" }), { props: { content: "ABCD" } }).x).toBe(100);
+    expect(applyObjectChanges(barcode({ fieldJustify: undefined }), { props: { content: "ABCD" } }).x).toBe(100);
+    expect(applyObjectChanges(barcode(), { props: { height: 80 } }).x).toBe(100);
+  });
+
+  it("skips edits that position the object themselves (transformer commits)", () => {
+    registerBarcodeWidthProber(probe);
+    const next = applyObjectChanges(barcode(), { x: 200, props: { content: "ABCD" } });
+    expect(next.x).toBe(200);
+  });
+
+  it("shifts y instead of x when the rotation swaps the axes", () => {
+    registerBarcodeWidthProber(probe);
+    const next = applyObjectChanges(barcode({}, { rotation: "R" }), { props: { content: "ABCD" } });
+    expect(next.x).toBe(100);
+    expect(next.y).toBe(30);
+  });
+
+  it("skips rotation changes (footprint axes swap, extents not comparable)", () => {
+    registerBarcodeWidthProber(probe);
+    const next = applyObjectChanges(barcode(), { props: { rotation: "R" } });
+    expect(next.x).toBe(100);
+    expect(next.y).toBe(50);
+  });
+
+  it("is inert without a registered prober (headless)", () => {
+    const next = applyObjectChanges(barcode(), { props: { content: "ABCD" } });
+    expect(next.x).toBe(100);
+  });
+
+  it("ignores non-1D types even with a hand-crafted justify (JSON/MCP)", () => {
+    registerBarcodeWidthProber(probe);
+    const qr = barcode({ type: "qrcode" });
+    expect(applyObjectChanges(qr, { props: { content: "ABCD" } }).x).toBe(100);
+  });
+
+  it("centre widen/narrow toggle returns exactly (no half-up walk)", () => {
+    // Odd delta (7) exposes Math.round's half-up asymmetry.
+    const oddProbe = (o: LabelObject) => {
+      const c = (o as { props: { content: string } }).props.content;
+      return { w: c === "long" ? 27 : 20, h: 30 };
+    };
+    registerBarcodeWidthProber(oddProbe);
+    const widened = applyObjectChanges(barcode({ fieldJustify: "C" }, { content: "shrt" }), {
+      props: { content: "long" },
+    });
+    const back = applyObjectChanges(widened, { props: { content: "shrt" } });
+    expect(back.x).toBe(100);
+  });
+
+  it("treats absent justify as L under ^FT+I (implicit == explicit)", () => {
+    registerBarcodeWidthProber(probe);
+    const implicit = barcode({ positionType: "FT", fieldJustify: undefined }, { rotation: "I" });
+    // Same compensation as explicit L: holding the left edge needs the delta.
+    expect(applyObjectChanges(implicit, { props: { content: "ABCD" } }).x).toBe(120);
+  });
+
+  it("inverts the shift under ^FT with rotation I (bar-width-dependent origin)", () => {
+    registerBarcodeWidthProber(probe);
+    const ftI = barcode({ positionType: "FT" }, { rotation: "I" });
+    // FT+I already pins the right edge; correct shift is 0.
+    expect(applyObjectChanges(ftI, { props: { content: "ABCD" } }).x).toBe(100);
+    const ftIL = barcode({ positionType: "FT", fieldJustify: "L" }, { rotation: "I" });
+    // Holding the LEFT edge under FT+I needs the full delta.
+    expect(applyObjectChanges(ftIL, { props: { content: "ABCD" } }).x).toBe(120);
+  });
+
+  it("applies the same inversion on the swapped axis under ^FT with rotation B", () => {
+    registerBarcodeWidthProber(probe);
+    const ftB = barcode({ positionType: "FT" }, { rotation: "B" });
+    // FT+B pins the justified edge on the y axis; right stays put.
+    const r = applyObjectChanges(ftB, { props: { content: "ABCD" } });
+    expect(r.x).toBe(100);
+    expect(r.y).toBe(50);
+    const ftBL = barcode({ positionType: "FT", fieldJustify: "L" }, { rotation: "B" });
+    expect(applyObjectChanges(ftBL, { props: { content: "ABCD" } }).y).toBe(70);
+  });
+});
+
+describe("symbology switch re-pin", () => {
+  afterEach(() => registerBarcodeWidthProber(null));
+
+  it("holds the justified edge when a type switch changes the width", () => {
+    const typedProbe = (o: LabelObject) =>
+      o.type === "code39" ? { w: 15, h: 30 } : { w: 20, h: 30 };
+    registerBarcodeWidthProber(typedProbe);
+    const src = barcode();
+    const next = anchorRepin(src, { props: {} }, convertSymbologyMapper("code39" as never)(src));
+    // Width 20 -> 15 with anchor R: origin moves right by the delta.
+    expect(next.x).toBe(105);
+  });
+});
+
+describe("prober registry", () => {
+  afterEach(() => registerBarcodeWidthProber(null));
+
+  it("a stale unregister cannot null a successor registration", () => {
+    const a = () => ({ w: 1, h: 1 });
+    const b = () => ({ w: 2, h: 2 });
+    registerBarcodeWidthProber(a);
+    registerBarcodeWidthProber(b);
+    unregisterBarcodeWidthProber(a);
+    expect(probeBarcodeFootprint({} as LabelObject)).toEqual({ w: 2, h: 2 });
+  });
+});
+
+describe("NON_EMITTING_PROP_KEYS", () => {
+  it("membership lock: exactly the editor-only, never-emitted prop keys", () => {
+    expect([...NON_EMITTING_PROP_KEYS].sort()).toEqual(["preSerialContent"]);
+  });
+});
+
+describe("valueAnchorShift", () => {
+  it("is symmetric for centre (away-from-zero halves)", () => {
+    expect(valueAnchorShift("C", 7, false)).toBe(4);
+    expect(valueAnchorShift("C", -7, false)).toBe(-4);
+  });
+
+  it("applies the FT I/B inversion", () => {
+    expect(valueAnchorShift("R", 10, true)).toBe(0);
+    expect(valueAnchorShift("L", 10, true)).toBe(-10);
+    expect(valueAnchorShift("C", 10, true)).toBe(-5);
+  });
+});
+
+describe("dirty semantics of fieldJustify", () => {
+  const asPage = (leaf: LabelObject) => ({ id: "p1", objects: [leaf] });
+  const stamp = (before: LabelObject, after: LabelObject) =>
+    (stampDirtyLeaves(
+      [asPage(before)] as Parameters<typeof stampDirtyLeaves>[0],
+      [asPage(after)] as Parameters<typeof stampDirtyLeaves>[1],
+    )[0]!.objects[0] as { dirty?: boolean }).dirty;
+
+  it("a 1D justify toggle does not stamp dirty (no z emitted yet; overlay survives)", () => {
+    const leaf = barcode();
+    // R, not only C: R is the value a future z-emit would make emit-affecting.
+    expect(stamp(leaf, { ...leaf, fieldJustify: "C" } as LabelObject)).toBeUndefined();
+    const noJustify = barcode({ fieldJustify: undefined });
+    expect(stamp(noJustify, { ...noJustify, fieldJustify: "R" } as LabelObject)).toBeUndefined();
+  });
+
+  it("a 2D justify change stamps dirty (fieldPosZ echoes the z)", () => {
+    const qr = barcode({ type: "qrcode", fieldJustify: undefined });
+    expect(stamp(qr, { ...qr, fieldJustify: "R" } as LabelObject)).toBe(true);
+  });
+
+  it("a graphic justify change stamps dirty (graphicAnchor emits it)", () => {
+    const box = barcode({ type: "box", fieldJustify: "L" });
+    expect(stamp(box, { ...box, fieldJustify: "R" } as LabelObject)).toBe(true);
+  });
+
+  it("a content change still stamps dirty", () => {
+    const leaf = barcode();
+    const changed = { ...leaf, props: { ...(leaf as { props: object }).props, content: "XYZ" } } as LabelObject;
+    expect(stamp(leaf, changed)).toBe(true);
+  });
+});
diff --git a/src/store/anchorRepin.ts b/src/store/anchorRepin.ts
new file mode 100644
index 00000000..a281ea7c
--- /dev/null
+++ b/src/store/anchorRepin.ts
@@ -0,0 +1,63 @@
+import type { LabelObject } from "@zplab/core/types/Group";
+import type { ObjectChanges } from "@zplab/core/types/LabelObject";
+import { BARCODE_1D_TYPES } from "@zplab/core/registry";
+import { isAxisSwapped, objectRotation } from "@zplab/core/registry/rotation";
+import { valueAnchorShift } from "@zplab/core/lib/valueAnchor";
+
+/** Rotated visual footprint in dots, as the canvas measures it. */
+interface BarcodeFootprint {
+  w: number;
+  h: number;
+}
+
+type BarcodeWidthProber = (obj: LabelObject) => BarcodeFootprint | null;
+
+/** Barcode width is not computable headlessly (bwip must encode), so the
+ *  canvas registers a synchronous prober at runtime; in node tests it stays
+ *  null and anchor re-pinning is simply off. */
+let prober: BarcodeWidthProber | null = null;
+
+export function registerBarcodeWidthProber(p: BarcodeWidthProber | null): void {
+  prober = p;
+}
+
+/** Clears only if `p` is still active, so a stale unmount cleanup can't null
+ *  a successor registration. */
+export function unregisterBarcodeWidthProber(p: BarcodeWidthProber): void {
+  if (prober === p) prober = null;
+}
+
+export function probeBarcodeFootprint(obj: LabelObject): BarcodeFootprint | null {
+  return prober ? prober(obj) : null;
+}
+
+/** Justified barcodes: shift the origin so a width-changing props edit keeps
+ *  the justified edge fixed. Skipped when the edit positions the object itself
+ *  (transformer commits carry x/y) and on rotation changes (axes swap). */
+export function anchorRepin(obj: LabelObject, changes: ObjectChanges, next: LabelObject): LabelObject {
+  // 1D-only: the ftFlip math matches barcodeFtAnchorOffset only there (QR
+  // graphics use an "N" offset + module shift the re-pin doesn't model);
+  // graphics have static extents, so fieldJustify never re-pins them.
+  if (!BARCODE_1D_TYPES.has(next.type)) return next;
+  // Absent means L (schema contract), and L participates under the FT flip.
+  const justify = next.fieldJustify ?? 'L';
+  const props = (next as { props: object }).props;
+  const rot = objectRotation(props);
+  // ^FT+I/B inverts the anchor math (see valueAnchorShift).
+  const ftFlip =
+    (next as { positionType?: string }).positionType === 'FT' && (rot === 'I' || rot === 'B');
+  if (justify === 'L' && !ftFlip) return next;
+  // `in`, not value-check: an explicit x/y key marks a positioning edit, and
+  // x: undefined is already illegal (the merge spread would clobber obj.x).
+  if (!changes.props || 'x' in changes || 'y' in changes) return next;
+  if ('rotation' in changes.props) return next;
+  // Both widths from the same synchronous probe: width-neutral edit = exact no-op.
+  const before = probeBarcodeFootprint(obj);
+  const after = probeBarcodeFootprint(next);
+  if (!before || !after) return next;
+  const swapped = isAxisSwapped(rot);
+  const delta = swapped ? before.h - after.h : before.w - after.w;
+  const shift = valueAnchorShift(justify, delta, ftFlip);
+  if (shift === 0) return next;
+  return swapped ? { ...next, y: next.y + shift } : { ...next, x: next.x + shift };
+}
diff --git a/src/store/dirtyTracking.ts b/src/store/dirtyTracking.ts
index 41059915..b32ff3ab 100644
--- a/src/store/dirtyTracking.ts
+++ b/src/store/dirtyTracking.ts
@@ -1,6 +1,7 @@
 import type { StateCreator, StoreMutatorIdentifier } from 'zustand';
 import { isGroup, type LabelObject, type Page } from '@zplab/core/types/Group';
-import { EMIT_AFFECTING_KEYS } from './labelStore.internals';
+import { emitsFieldJustify } from '@zplab/core/registry';
+import { EMIT_AFFECTING_KEYS, NON_EMITTING_PROP_KEYS } from './labelStore.internals';
 
 // Centralizes round-trip dirty-tracking that was otherwise scattered across every
 // object mutator (the chokepoint plus each wholesale-rewrite bypass). A single
@@ -10,14 +11,24 @@ import { EMIT_AFFECTING_KEYS } from './labelStore.internals';
 // temporal, so zundo's restore path (which replays via the original setState,
 // outside this wrapper) does not re-stamp on undo/redo.
 
-/** True when any emit-affecting field differs. Scalars compare by value; `props`
- *  compares by reference. Given the store's identity-preserving mutators (which
- *  keep the same `props` object when nothing changed and produce a fresh one on
- *  an edit), this never UNDER-stamps; it can only over-stamp on a no-op props
- *  rebuild, which merely regenerates a byte-identical field. Reuses the single
- *  EMIT_AFFECTING_KEYS source. */
+/** True when any emit-affecting field differs. Scalars compare by value;
+ *  props diffs shallowly (editor-aid keys skipped) and relies on mutators
+ *  replacing, never mutating, nested prop values. */
 function emitAffectingChanged(a: LabelObject, b: LabelObject): boolean {
   for (const k of EMIT_AFFECTING_KEYS) {
+    const av = (a as Record<string, unknown>)[k];
+    const bv = (b as Record<string, unknown>)[k];
+    if (av === bv) continue;
+    if (k === 'fieldJustify' && !emitsFieldJustify(b.type)) continue;
+    if (k === 'props' && !propsEmitChanged(av as object, bv as object)) continue;
+    return true;
+  }
+  return false;
+}
+
+function propsEmitChanged(a: object = {}, b: object = {}): boolean {
+  for (const k of new Set([...Object.keys(a), ...Object.keys(b)])) {
+    if (NON_EMITTING_PROP_KEYS.has(k)) continue;
     if ((a as Record<string, unknown>)[k] !== (b as Record<string, unknown>)[k]) return true;
   }
   return false;
diff --git a/src/store/labelStore.internals.ts b/src/store/labelStore.internals.ts
index b7b6bfa7..0fb776f9 100644
--- a/src/store/labelStore.internals.ts
+++ b/src/store/labelStore.internals.ts
@@ -4,6 +4,7 @@ import { isLocaleCode, type LocaleCode } from '../locales';
 import { renameTemplateMarkers, substituteTemplateMarker } from '@zplab/core/lib/fnTemplate';
 import { getObjectStringContent } from '@zplab/core/lib/variableBinding';
 import { getEntry } from '@zplab/core/registry';
+import { anchorRepin } from './anchorRepin';
 
 /** Meta fields that remain editable on a locked object so the user can
  *  release the lock or annotate without unlocking first. Everything else
@@ -28,6 +29,11 @@ export const EMIT_AFFECTING_KEYS = new Set(['x', 'y', 'rotation', 'positionType'
  *  wrongly added here would silently skip the overlay drop and emit stale config. */
 export const NON_EMITTING_CONFIG_KEYS = new Set(['safeAreaMm']);
 
+/** Prop keys that never reach emitted ZPL: a props diff touching only these
+ *  must not stamp dirty and drop the verbatim overlay. Classifies globally by
+ *  key name (membership locked in anchorRepin.test.ts). */
+export const NON_EMITTING_PROP_KEYS = new Set(['preSerialContent']);
+
 /** True when a config patch changes a field that reaches emitted ZPL. Used to
  *  drop page overlays: until config-segment linkage lands, an overlay replays
  *  config verbatim, so an emit-affecting edit must force full regeneration. */
@@ -144,7 +150,7 @@ export function applyObjectChanges(
   } as LabelObject;
   // Dirty-tracking is centralized in the dirtyTracking middleware (a state diff),
   // so this mutator no longer stamps dirty itself.
-  return next;
+  return anchorRepin(obj, normalized, next);
 }
 
 export function detectLocale(): LocaleCode {
diff --git a/src/store/slices/objectSlice.ts b/src/store/slices/objectSlice.ts
index c2545c0c..28d3fdd5 100644
--- a/src/store/slices/objectSlice.ts
+++ b/src/store/slices/objectSlice.ts
@@ -13,6 +13,7 @@ import {
   type Page,
 } from '@zplab/core/types/Group';
 import { getEntry } from '@zplab/core/registry';
+import { anchorRepin } from '../anchorRepin';
 import { reorderForZ, type ZOrderDir } from '../../lib/zorder';
 import { makeReverseBackingBox, precedingBackingExists, isOwnReverseBacking } from '@zplab/core/lib/reverseBacking';
 import { spawnRotationOverride } from '../../lib/spawn';
@@ -204,7 +205,12 @@ export const createObjectSlice: StateCreator<LabelState, [], [], ObjectSlice> =
       // design; the mapper owns the result's validity (line/box have no hook).
       // The type/props change is stamped dirty centrally by the dirtyTracking
       // middleware.
-      const next = mapObjectById(objs, id, (o) => mapper(o));
+      // anchorRepin still runs: a type switch changes the measured width, so
+      // the justified edge must hold like on any value edit.
+      const next = mapObjectById(objs, id, (o) => {
+        const mapped = mapper(o);
+        return mapped === o ? o : anchorRepin(o, { props: {} }, mapped);
+      });
       // A no-op mapper must not rebuild pages: the fresh array would record a
       // phantom undo step (temporalEquality is a ref compare).
       if (next === objs) return {};