Keyboard Test
Press every key and watch it light up. Find dead keys, keys that register twice and how many keys your keyboard can handle at once.
- Full-size layout
- Rollover & ghosting
- Chatter detection
- key / code / keyCode
What is a keyboard test?
A keyboard test shows which keys your computer receives as you press them. This tester draws a full-size layout with function keys, navigation cluster and number pad. Each key turns blue while pressed and green once it has registered. It counts the most keys held at the same time (key rollover), flags chatter when a key fires twice within 40 ms of being released, which is a common mechanical-switch fault, and logs the JavaScript key, code, keyCode and location of every press for developers.
How to test your keyboard
- Click the keyboard picture so the test has focus.
- Press every key once. Keys turn green when they register; any that stay grey are not reaching the computer.
- For gaming keyboards, hold several keys together, such as W, A, S, D and Space, and check the Max at once count.
- If a key is highlighted amber, press it slowly several times. Repeated chatter warnings point to a dirty or worn switch.
Reading the results
- Grey key after pressing: the key is not reaching the computer. Try another USB port, clean under the keycap, or check whether the key is remapped.
- Amber key: chatter. The switch bounced and registered twice. Compressed air or switch cleaner often fixes it; otherwise replace the switch.
- Low Max at once: if three keys pressed together register as two, the keyboard has limited rollover (ghosting). Many office keyboards support 2–6 keys; gaming keyboards often support all.
- Fn, media and some system keys never reach the browser. Windows and macOS keep them, so they cannot be tested here.
Why use this keyboard test
- Nothing leaves your deviceWhat you type is processed by your browser on this device. There is no upload, no server-side recording and no account.
- Catches real faultsChatter detection and rollover counts find problems that a simple “key lights up” test misses.
- Developer key codesSee KeyboardEvent.key, code, keyCode and location for every press, handy for shortcuts and games.
- No download or driverRuns in Chrome, Edge, Firefox and Safari on Windows, macOS, Linux, ChromeOS, Android and iPhone.
When to run a keyboard test
- Spilled drink or sticky keys. Find exactly which keys stopped working.
- New or second-hand keyboards. Check every key before the return window closes.
- Mechanical keyboard chatter. Confirm double typing before cleaning or replacing a switch.
- Gaming. Test anti-ghosting for the key combinations your games use.
Checking a whole setup? Run the mic test, webcam test, mouse test, gamepad tester, sound test, dead pixel test and refresh rate test, or browse all device tests.
Example: the E key types “ee”
Press E slowly ten times. If the key turns amber and the log shows “chatter?”, the switch is bouncing. Blow out the switch, test again, and if the warning returns, replace the switch or use the keyboard’s debounce setting if it has one.
What to expect from the result
The browser only sees keys the operating system passes on. Fn, media keys, Windows+L, ⌘+Tab and similar shortcuts are handled by the system. Rollover is limited by both the keyboard and USB mode, and Bluetooth keyboards may report fewer simultaneous keys.
Keyboard Test questions
How do I test my keyboard keys?
Click the keyboard on this page and press each key. Keys turn green when they register. Any key that stays grey after pressing is not working.
How do I test keyboard ghosting?
Hold several keys at once, such as W, A, S, D, Shift and Space. Max at once shows how many registered together. If keys stop lighting up as you add more, the keyboard has limited rollover.
What is key chatter?
Chatter is when one press registers as two or more because the switch contacts bounce. This test flags a key that fires again within 40 milliseconds of being released.
Why do some keys not light up?
Keys such as Fn, media controls and system shortcuts are handled by your operating system and never reach the browser. For other keys, a grey result means the press is not being received.
Does this keyboard tester record what I type?
No. Key presses are shown on screen only and are not stored or sent anywhere. The log keeps the last 40 presses in this tab and clears when you reset or leave.