diff --git a/src/components/AboutDialog.test.tsx b/src/components/AboutDialog.test.tsx
index 95c32fb..4f7c06a 100644
--- a/src/components/AboutDialog.test.tsx
+++ b/src/components/AboutDialog.test.tsx
@@ -1,5 +1,6 @@
 import { fireEvent, render, screen, waitFor } from "@testing-library/react";
 import { afterEach, describe, expect, it, vi } from "vitest";
+import * as checkUpdate from "../lib/check-update";
 import * as tauri from "../lib/tauri";
 import { AboutDialog } from "./AboutDialog";
 
@@ -7,6 +8,15 @@ afterEach(() => {
   vi.restoreAllMocks();
 });
 
+const release = (version: string) => ({
+  tagName: `v${version}`,
+  version,
+  htmlUrl: `https://github.com/oratis/Markup/releases/tag/v${version}`,
+  publishedAt: "2026-01-01T00:00:00Z",
+  name: null,
+  body: null,
+});
+
 describe("AboutDialog", () => {
   it("shows the bundle id and renders the version once getVersion resolves", async () => {
     vi.spyOn(tauri, "getVersion").mockResolvedValue("0.9.9");
@@ -34,4 +44,38 @@ describe("AboutDialog", () => {
     fireEvent.click(screen.getByText(/^close$/i));
     expect(onClose).toHaveBeenCalled();
   });
+
+  it("Check for Updates reports when you're on the latest version", async () => {
+    vi.spyOn(tauri, "getVersion").mockResolvedValue("1.0.0");
+    vi.spyOn(checkUpdate, "checkUpdateAgainstGithub").mockResolvedValue({
+      hasUpdate: false,
+      current: "1.0.0",
+      latest: release("1.0.0"),
+      dismissed: false,
+    });
+    render(<AboutDialog onClose={() => {}} />);
+    fireEvent.click(screen.getByText("Check for Updates"));
+    await waitFor(() =>
+      expect(screen.getByText("You're on the latest version")).toBeInTheDocument(),
+    );
+  });
+
+  it("Check for Updates surfaces a newer release as a Get button", async () => {
+    vi.spyOn(tauri, "getVersion").mockResolvedValue("1.0.0");
+    vi.spyOn(checkUpdate, "checkUpdateAgainstGithub").mockResolvedValue({
+      hasUpdate: true,
+      current: "1.0.0",
+      latest: release("1.1.0"),
+      dismissed: false,
+    });
+    render(<AboutDialog onClose={() => {}} />);
+    fireEvent.click(screen.getByText("Check for Updates"));
+    await waitFor(() => expect(screen.getByText("Get v1.1.0")).toBeInTheDocument());
+  });
+
+  it("always offers a Changelog link", () => {
+    vi.spyOn(tauri, "getVersion").mockResolvedValue("1.0.0");
+    render(<AboutDialog onClose={() => {}} />);
+    expect(screen.getByText("Changelog")).toBeInTheDocument();
+  });
 });
diff --git a/src/components/AboutDialog.tsx b/src/components/AboutDialog.tsx
index 17aa293..453212d 100644
--- a/src/components/AboutDialog.tsx
+++ b/src/components/AboutDialog.tsx
@@ -1,4 +1,6 @@
+import { openUrl } from "@tauri-apps/plugin-opener";
 import { useEffect, useState } from "react";
+import { type LatestRelease, checkUpdateAgainstGithub } from "../lib/check-update";
 import { useT } from "../lib/i18n";
 import { getVersion } from "../lib/tauri";
 
@@ -7,11 +9,20 @@ interface Props {
 }
 
 const REPO_URL = "https://github.com/oratis/Markup";
+const RELEASES_URL = `${REPO_URL}/releases`;
 const BUNDLE_ID = "com.appkon.markup";
 
+type UpdateState =
+  | { kind: "idle" }
+  | { kind: "checking" }
+  | { kind: "upToDate" }
+  | { kind: "available"; latest: LatestRelease }
+  | { kind: "error" };
+
 export function AboutDialog({ onClose }: Props) {
   const t = useT();
   const [version, setVersion] = useState<string>("…");
+  const [update, setUpdate] = useState<UpdateState>({ kind: "idle" });
 
   useEffect(() => {
     getVersion()
@@ -19,6 +30,18 @@ export function AboutDialog({ onClose }: Props) {
       .catch(() => setVersion("dev"));
   }, []);
 
+  const openExternal = (url: string) => {
+    openUrl(url).catch((e) => console.warn("about: failed to open url", e));
+  };
+
+  const checkUpdates = async () => {
+    setUpdate({ kind: "checking" });
+    const r = await checkUpdateAgainstGithub();
+    if (!r.latest) setUpdate({ kind: "error" });
+    else if (r.hasUpdate) setUpdate({ kind: "available", latest: r.latest });
+    else setUpdate({ kind: "upToDate" });
+  };
+
   return (
     <div
       className="fixed inset-0 bg-black/40 flex items-center justify-center z-50"
@@ -37,15 +60,48 @@ export function AboutDialog({ onClose }: Props) {
             </div>
             <div className="font-mono">{BUNDLE_ID}</div>
           </div>
+
+          {/* Update check + changelog */}
+          <div className="mt-5 flex flex-col items-center gap-2 text-[12px]">
+            {update.kind === "available" ? (
+              <button
+                onClick={() => openExternal(update.latest.htmlUrl)}
+                className="px-3 py-1 rounded bg-blue-500 text-white hover:bg-blue-600"
+              >
+                {t("about.updateAvailable", update.latest.tagName)}
+              </button>
+            ) : (
+              <button
+                onClick={checkUpdates}
+                disabled={update.kind === "checking"}
+                className="px-3 py-1 rounded border border-black/10 dark:border-white/20 hover:bg-black/5 dark:hover:bg-white/10 disabled:opacity-50"
+              >
+                {update.kind === "checking"
+                  ? t("about.checking")
+                  : t("about.checkUpdates")}
+              </button>
+            )}
+            {update.kind === "upToDate" && (
+              <div className="opacity-60">{t("about.upToDate")}</div>
+            )}
+            {update.kind === "error" && (
+              <div className="opacity-60">{t("about.checkFailed")}</div>
+            )}
+            <button
+              onClick={() => openExternal(RELEASES_URL)}
+              className="underline opacity-70 hover:opacity-100"
+            >
+              {t("about.changelog")}
+            </button>
+          </div>
+
           <div className="mt-5 text-[11px]">
-            <a
-              href={REPO_URL}
-              target="_blank"
-              rel="noreferrer"
+            <button
+              onClick={() => openExternal(REPO_URL)}
               className="underline opacity-80 hover:opacity-100"
             >
               {REPO_URL}
-            </a>
+            </button>
           </div>
           <button
             onClick={onClose}
diff --git a/src/lib/locales/en.ts b/src/lib/locales/en.ts
index af02f56..297d7e7 100644
--- a/src/lib/locales/en.ts
+++ b/src/lib/locales/en.ts
@@ -68,6 +68,12 @@ export const en = {
   "about.tagline": "High-performance Markdown editor for macOS",
   "about.version": "Version",
   "about.close": "Close",
+  "about.checkUpdates": "Check for Updates",
+  "about.checking": "Checking…",
+  "about.upToDate": "You're on the latest version",
+  "about.updateAvailable": "Get {0}",
+  "about.checkFailed": "Couldn't check for updates",
+  "about.changelog": "Changelog",
 
   // command palette / quick open
   "palette.placeholder": "Run a command…",
diff --git a/src/lib/locales/zh.ts b/src/lib/locales/zh.ts
index 4054b50..6e83f55 100644
--- a/src/lib/locales/zh.ts
+++ b/src/lib/locales/zh.ts
@@ -69,6 +69,12 @@ export const zh: Strings = {
   "about.tagline": "面向 macOS 的高性能 Markdown 编辑器",
   "about.version": "版本",
   "about.close": "关闭",
+  "about.checkUpdates": "检查更新",
+  "about.checking": "检查中…",
+  "about.upToDate": "已是最新版本",
+  "about.updateAvailable": "获取 {0}",
+  "about.checkFailed": "无法检查更新",
+  "about.changelog": "更新日志",
 
   // command palette / quick open
   "palette.placeholder": "运行命令…",