Keyboard tester

The big number is how many different keys sent a signal. There is no right number, because keyboards differ: a small laptop keyboard has far fewer keys than a full one, and the picture shows one standard layout. A key that does not light up when you press it sent nothing to the browser. That may be a worn or dirty switch, but it may also be a key the system keeps for itself.

Most keys at once shows how many keys you held together, and the result sets it beside a reference fact: a keyboard in the basic USB mode reports up to 6 (as the standard sets it)^[1] keys at once besides Shift, Ctrl and Alt^[1]. Many keyboards report more outside that mode, and some cheap ones fewer in some combinations, which matters when you play games that need several keys together. A possible bounce is a press that arrived very soon after the same key came up. It can mean a worn switch, but two fast presses look the same, so run the test again before you decide.

While the test is on, the page listens for key events that come from your own hands and ignores those a script makes. It stops every key from doing its usual job, so that Tab, Space and the arrow keys light their keys instead of moving the page. A browser keeps some shortcuts for itself, such as closing a tab, and these cannot be stopped.

The picture is a full-size keyboard with one standard layout. If your keyboard is laid out differently, keys still light in the same places and show the character your keyboard reports once you press them. A key the picture has no place for is listed under it by its code. Your result is kept in this browser only; you can read about us to see who makes the site.

• Press it again, a little harder and in the middle of the key, to rule out a slip.
• Check that the keyboard is connected: a loose cable or a flat battery makes keys drop out.
• Look for crumbs or dust under the key and clean it with a soft brush or compressed air.
• Try the keyboard on another computer, or another keyboard on this one, to find out which of the two is at fault.

Some keyboards cannot tell certain combinations apart, because of the way their keys are wired. When you press three or four keys together, one may seem to be missing. A keyboard built for games usually sends every combination; an office keyboard often does not. The number of keys at once in your result shows what your keyboard did in this check.