Keyboard Tester

Your computer is probably set to a different keyboard layout or language than your keyboard. Open your keyboard or language settings, choose the layout printed on your keys (for example US QWERTY) and remove layouts you don't use. If it still happens, reinstall the keyboard driver from your manufacturer's website.

Reconnect the keyboard or try another USB port. For a wireless keyboard, replace the batteries and pair it again. Then test it on another computer: if the key works there, the cause is a driver or setting on your computer; if it fails there too, the key or switch is faulty.

Unplug or switch off the keyboard, turn it upside down and tap it gently to release crumbs, then blow compressed air between the keys. Clean sticky keys with a cotton swab lightly dampened with isopropyl alcohol. After a sugary spill, the keyboard may need a deep clean or replacing.

Use it when a key stops working, types twice or feels sticky, when you buy a new or used keyboard, to check ghosting on a gaming keyboard, and to test keys you can't easily type into a document, such as F1 to F12, Print Screen or the numpad.

Yes. Switch the tester to Mac to show the Command and Option keys, or choose TKL or 60% for smaller keyboards. Laptop keyboards work too, but the Fn key itself can't be detected because the keyboard handles it internally.

Press every key once. Each key lights up red while you press it and stays tinted afterwards, and the counter shows how many keys you have tested. When every key is tinted, your keyboard has passed.

Warning signs are keys that never light up, keys that need extra force, keys that register twice from one press (the tester warns you about this key chatter) and keys that stay pressed after you let go. If keys also fail on another computer, it is time to repair or replace the keyboard.

Yes. This tester runs entirely in your browser and never records or sends what you type, so you can safely press any key.