Set autoComplete="off" in date pickers

CHANGELOG.md

@@ -38,6 +38,7 @@ This project adheres to [Semantic Versioning](https://semver.org/).
 - [#3881](https://github.com/plotly/dash/pull/3881) Fix components rendered as props (eg. `dcc.Dropdown` option labels, `dcc.Tab` labels) crashing or failing to update when the host subtree was replaced by a callback; out-of-tree `ExternalWrapper` components now re-insert themselves and update in place.
 - [#3929](https://github.com/plotly/dash/issues/3929) Fix components that set their own initial state on mount (eg. `dash-bootstrap-components` `Tabs`) not applying it on first render, because descendant layout hashes were reset on the first fresh render (regression introduced in 4.2.0 by [#3570](https://github.com/plotly/dash/pull/3570)).
 - [#3948](https://github.com/plotly/dash/issues/3948) Fix page getting progressively slower as callbacks append children
+- [#4009](https://github.com/plotly/dash/issues/4009) Disable autocomplete in DatePickerSingle and DatePickerRange inputs.
 - [#3002](https://github.com/plotly/dash/issues/3002) Fix page loads failing with a 500 error on Windows when Dash is imported from an extended-length (`\\?\`) path, as in JupyterLab Desktop. Package resource paths are now joined with the OS separator instead of `/`.
 
 ## [4.4.1] - 2026-07-21

components/dash-core-components/src/fragments/DatePickerRange.tsx

@@ -105,8 +105,8 @@
     const containerRef = useRef<HTMLDivElement>(null);
     const startInputRef = useRef<HTMLInputElement | null>(null);
     const endInputRef = useRef<HTMLInputElement | null>(null);
     const startAutosizeRef = useRef<any>(null);
     const endAutosizeRef = useRef<any>(null);
     const calendarRef = useRef<CalendarHandle>(null);
     const isNewRangeRef = useRef(false);
     const hasPortal = with_portal || with_full_screen_portal;
@@ -405,6 +405,7 @@
                             disabled={disabled}
                             dir={direction}
                             aria-label={start_date_placeholder_text}
+                            autoComplete="off"
                         />
                         <ArrowIcon className="dash-datepicker-range-arrow" />
                         <AutosizeInput
@@ -427,6 +428,7 @@
                             disabled={disabled}
                             dir={direction}
                             aria-label={end_date_placeholder_text}
+                            autoComplete="off"
                         />
                         {clearable && !disabled && (
                             <a

components/dash-core-components/src/fragments/DatePickerSingle.tsx

@@ -64,7 +64,7 @@
 
     const containerRef = useRef<HTMLDivElement>(null);
     const inputRef = useRef<HTMLInputElement | null>(null);
     const autosizeRef = useRef<any>(null);
     const calendarRef = useRef<CalendarHandle>(null);
     const hasPortal = with_portal || with_full_screen_portal;
 
@@ -204,6 +204,7 @@
                             disabled={disabled}
                             dir={direction}
                             aria-label={placeholder}
+                            autoComplete="off"
                         />
                         {clearable && !disabled && !!date && (
                             <a