How do I change what a mouse button does on my computer?

Start by naming the change you want: swap which button is primary, or make an extra button perform a different action. Those are different settings, and your computer may offer one without offering the other.

If you use Windows 10 or Windows 11 and want to swap the primary button, open Mouse settings and choose Left or Right for the primary button. Microsoft documents that built-in option, while noting that available options can depend on the Windows version and device. [S1]

Try the setting with a simple task, such as selecting an item, then check that the other click still does what you expect. If you only meant to change pointer speed or wheel behavior, those are separate mouse settings—not button assignments.

Possibly, but the Windows primary-button choice only swaps Left and Right; it does not establish that Windows can assign any action to every extra button. [S1] Check the mouse’s own configuration app or documentation for options to assign actions to its additional buttons. If you do not know the mouse model, look for its name or model number on the device or packaging; use a placeholder such as [mouse model] when searching its documentation.

Before changing anything, note the button’s current behavior and the action you want. Change one button at a time, apply the change, then test it in a place where an accidental click will not submit, delete, or send something. If no supported assignment option is listed, do not assume that a setting exists.

In Windows 10 or Windows 11, open Mouse settings and select Left or Right for the primary button. [S1] The setting is specifically about which button is primary; it is not the same as assigning a custom command to a side button. The cited Windows guidance confirms the primary-button swap, but it does not establish every detail of secondary-click behavior for each mouse, application, or device.

After changing it, try selecting a harmless item and opening a harmless context menu, if that is part of your usual work. If the result is confusing, return to Mouse settings and check which primary option is selected. Menu names and available choices may differ by Windows version or device, so if you cannot find the option, search your system’s settings for “Mouse” rather than following instructions for a different operating system.

Use this copyable plan:

1. Goal: [swap primary buttons / assign an action to an extra button]
2. Device and system: [mouse model] / [operating system and version]
3. Current behavior: [what the button does now]
4. Desired behavior: [what you want it to do]
5. Setting checked: [Mouse settings / mouse configuration app / documentation]
6. Test: [safe action tried] → [result]

For the Windows primary-button swap, choose Left or Right in Mouse settings. [S1] For a different assignment, check whether your specific mouse offers it; the cited Windows guidance does not confirm arbitrary reassignment or provide a full guide to secondary clicks. If you cannot identify a supported option, keep the current configuration and consult the mouse’s documentation.