Windows 10 does not provide a separate setting to change only the width of the Start/search menu. The Start menu (and the integrated search UI) can be resized by dragging its borders, but this affects the whole menu, not just the search area.
To adjust what is possible:
- Open Start.
- Move the pointer to the top or side border until it becomes a double‑headed arrow.
- Drag to resize the Start menu; the search panel follows this size.
If the overall UI elements feel too large, adjust system scaling instead:
- Select Start > Settings > System > Display.
- Under Scale & layout, choose a smaller Scale percentage.
There is no built‑in option in Windows 10 to independently reduce the width of just the search popup beyond these Start menu and display-scaling controls.
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