Test every key on your keyboard, including left and right Shift, Ctrl and Alt, with rollover and key chatter detection
How to use
Press each key on your keyboard. It lights up while held and turns green once it has worked.
Check the counter at the top to see how many keys you have tested, and look for any key that stays grey.
Hold down several keys at once to find how many your keyboard can register together.
Watch for amber warnings: a key that fires twice from one press is chattering.
Why use this tool
Left and right keys, told apart: Left and right Shift, Ctrl, Alt and Windows keys, and the keypad Enter, are each tested separately, because each has its own switch.
Finds chattering switches: A key that sends a second press within 40 milliseconds of being released is flagged, which is the signature of a dirty or worn mechanical switch.
Rollover test: See the largest number of keys your keyboard registered at once, and which keys they were, to check for ghosting in games.
Works with any language layout: Keys are matched by physical position, so AZERTY, QWERTZ and other layouts light up the right keys.
Details for developers: A live log shows key, code, keyCode, location, repeat and the time between events for every press and release.
Frequently asked questions
How do I test if every key on my keyboard works?
Press every key once. Each working key turns green and the counter goes up. Any key that stays grey after you press it is not reaching the computer.
Why does a key not light up?
Some keys never reach a web page: Fn is handled inside the keyboard, and the system keeps some shortcuts such as the Windows key or Print Screen on some computers. For other keys, try another USB port or cable, and check the keyboard's own settings software.
What is key chatter?
Chatter is when one press of a key registers as two or more. It is common on worn or dusty mechanical switches. Blowing out the switch, reseating the keycap, or replacing the switch usually fixes it.
What is keyboard rollover or ghosting?
Rollover is how many keys a keyboard can register at the same time. Cheaper keyboards may miss a key when several are held together, which is called ghosting or blocking. Hold down a group of keys and see which ones light up.
Why can't the tester see the difference between my two Enter keys on another site?
Older testers read the character a key types, which is the same for both. This one reads the physical key, so both Enter keys, and left and right modifiers, are shown separately.
Can I test a keyboard on a phone or tablet?
Yes, with a physical keyboard connected by Bluetooth or USB. The on-screen keyboard of a phone does not send physical key events.