In computing, the menu key or application key (≣ Menu) is a key previously found on Microsoft Windows-oriented computer keyboards. It was introduced at the same time as the Windows logo key. On keyboards including the key, its symbol would usually be a small icon depicting a pointer hovering above a menu; it would typically be found on the right side of the keyboard between the right Windows logo key and the right control key (or between the right AltGr key and the right control key). While the Windows key is present on the vast majority of keyboards intended for use with the Windows operating system, the menu key was frequently omitted in the interest of space, particularly on portable and laptop keyboards.

The key's primary function was to launch a context menu with the keyboard rather than with the usual right-mouse button.^[1] It was able to be used when the right-mouse button was not present on a mouse.

Some Windows public terminals did not have a Menu key on their keyboard with the goal of preventing users from right-clicking; however, in many Windows applications, a similar functionality could be invoked with the ⇧ Shift+F10 keyboard shortcut, or sometimes Ctrl+⇧ Shift+F10.

Some laptop computers include a menu function on the fn key (usually operated by typing ⇧ Shift+Fn), however, this generally invokes functions built into the vendor's software and is not the same as the key described above. For example, the Logitech Illuminated Keyboard has an FN key where the menu key is usually found; pressing FN, together with the keyboard's print screen key (above home), produces the Menu key function.

Programmers using the Windows API can intercept this key by looking for a WM_KEYDOWN message with wParam VK_APPS (defined as 0x5D in winuser.h). It has key code 93 (VK_APPS 0x5D).^{[needs update?]}

Android devices formerly came with physical Menu buttons, but with the release of Android Honeycomb, this was deprecated in favor of an on-screen button.^[2][3]

In January 2024, Microsoft announced a Microsoft Copilot key that would replace the menu key on devices promoted as "AI PCs". If Copilot is disabled or not available in the user's market, this key would launch Windows Search.^[4][5]