What the Alt key does
Alt (alternate) changes what other keys do. Held with the numeric keypad it enters Alt codes for symbols. Alt+Tab switches windows, Alt+F4 closes them, and Alt on its own moves focus to an app's menu bar so you can press the underlined letters.
On a Mac
Apple calls the equivalent key Option (⌥). Mac shortcuts that mirror Windows Alt shortcuts usually use Option, though Alt+Tab becomes Command+Tab.
On a laptop
Both Alt keys are normally present. The right Alt is often labelled Alt Gr on UK and European laptops and types the third character printed on a key (€, @, accented letters).
Shortcuts that use the Alt key
| Shortcut | What it does |
|---|---|
| Alt+Tab | Switch between open windows |
| Alt+F4 | Close the current window |
| Alt+0176 (numpad) | Degree symbol ° via Alt code |
| Alt+Enter | Properties in Explorer, full screen in some apps |
| Alt+Print Screen | Screenshot only the active window |
| Alt+letter | Open a menu with that underlined letter |
If the Alt key is missing or not working
If Alt codes do not work, Num Lock is usually off or the laptop has no numpad. If Alt+Tab fails, a game or remote session may be capturing it. Test both Alt keys below; the right one reports as Alt Gr on some layouts.
Test it here: click the tester, press the key, and it should light up green. A red key is stuck; a key that never lights up is dead or intercepted by the system. The full keyboard tester has the press log and more detail.
Click the tester, then press any key. Browser shortcuts are blocked while it has focus.
—
- key
- —
- code
- —
- keyCode
- —
none
Max at once: 0 (rollover)
None detected. A key held for more than 2 seconds is flagged.
Frequently asked questions
What is the Alt key on a Mac? +
The Option key (⌥). It is in the same place, between control and command.
What is the difference between Alt and Alt Gr? +
Alt Gr is the right Alt key on international layouts. It types the third symbol printed on a key, such as € or @, and equals Ctrl+Alt on Windows.
Why does Alt+Tab not work? +
A full-screen game or remote desktop can capture it, or a stuck Alt key is confusing Windows. Tap both Alt keys, then try again.
How do I use Alt codes? +
Hold Alt, type the code on the numeric keypad with Num Lock on, then release Alt. See the Alt codes finder for every code.