Keyboard Tester
Press any key — dead keys stay dark
Click here first, then press keys. Green = works. If a key never lights up, it may be dead.
What is the Keyboard Tester?
How It Works
Press any key on your physical keyboard and the matching key lights up on screen. Keys you have pressed stay green, so you can systematically walk the whole board and spot dead keys that never light up.
What You Can Diagnose
Dead keys (no response), stuck keys (stay lit without being held), chattering keys (fire repeatedly), and rollover limits — hold multiple keys and watch the Held Now counter to see how many simultaneous presses your keyboard reports.
Testing Tips
Test after spills or cleaning, before selling or buying a used keyboard, and when a game input feels unreliable. Browser and OS may reserve a few combos (like Cmd+Q) — test modifier keys individually.
FAQ
A key lights up but types the wrong character?
The tester shows physical key codes — wrong characters point to layout settings, not hardware.
How many keys should light simultaneously?
Budget keyboards often report 6 (6-key rollover); gaming keyboards with NKRO report every key.
Does it cover laptop keyboards?
Yes, any keyboard the OS sees.
Is it free?
Yes, completely free.