Keyboard Tester for Mac
Press any key on your Mac keyboard to check it works.
Browsers can't detect this key
macOS may keep this key unless you hold fn
Ready.
Every test runs inside your browser. Nothing you type, say, show or press is uploaded.
How to use this test
This keyboard tester for Mac draws a Mac keyboard with Command, Option, Control and the half-height arrow keys, and lights each key as you press it. Use it to find dead or sticky keys on a MacBook or a Magic Keyboard. Keys a browser can't see are marked, so they don't look broken.
Click the keyboard picture so it has focus, then press each key once. Pick Mac ANSI for a US keyboard or Mac ISO for a UK or European one. A key sinks while you hold it and stays lit once tested. Caps Lock lights as soon as you press it, because macOS reports it differently. Skip shortcuts that close the page, such as Command-W and Command-Q.
What the results mean
The picture shows the compact Mac layout, so keys found only on the larger Magic Keyboard with Numeric Keypad, such as the number pad, Home, End and forward delete, aren't drawn. Any key on the picture that never lights up isn't reaching the browser. Try it in another app too: if it fails everywhere, the key or the keyboard needs a repair. Keys with a dashed outline, fn (Globe) and the Touch ID or power key, can't be detected by a web page. Striped F-keys only register when macOS passes them on; the first question below explains how.
Testing a MacBook keyboard or a Magic Keyboard
The built-in keyboard on a MacBook and a separate Magic Keyboard both work with this Mac keyboard test. On a MacBook, disconnect any external keyboard first, so you know every press comes from the built-in one.
If several keys stop working at once on a Magic Keyboard, charge it and connect it with its cable before you test again. That rules out a flat battery or a weak Bluetooth connection. If a single key also fails in other apps, the problem is that key.
Mac ANSI or ISO, and two keys that can look swapped
Mac ANSI keyboards, the US layout, have a wide single-row return key. Mac ISO keyboards, used in the UK and much of Europe, have a tall return key and an extra key next to the left Shift. Pick the one that matches yours so the right keys are drawn.
In Safari, the key left of 1 and the key left of Z can light up the wrong way round on some ISO keyboards. That's a known Safari bug, not a fault in your keyboard. If it happens, check those two keys in Chrome or Firefox.
Common questions
The F1 to F12 keys don't light up.
By default the top row controls brightness, volume, Mission Control and other Mac features, and macOS handles those itself. Hold fn while you press F1 to F12, or turn on Use F1, F2, etc. keys as standard function keys in System Settings > Keyboard > Keyboard Shortcuts > Function Keys.
Why can't the tester see the fn or Globe key?
Most browsers on macOS never get an event for fn on its own, because the key changes what other keys do. To check it with the default settings, hold fn and press a key in the top row. If that key lights up as an F-key, fn works.
A key looks stuck while I hold Command.
While Command is held, macOS doesn't tell the browser when other keys are released. The tester clears them as soon as you let go of Command, so the key isn't faulty.