Keyboard Tester
Guide & FAQ- Pressed now
- 0
- Max at once
- 0
- Keys tested
- 0
- Last key
- -
- Held together
- -
Tip: hold as many keys as you can. If Max at once is lower than the number of keys you hold, your keyboard dropped some (ghosting).
Other keys:
Event log
| Time | Event | key | code | Gap |
|---|
Press a key to see events here.
Guide: Keyboard Tester
How to test your keyboard
Click the on-screen keyboard once to give it focus, then press the keys on your real keyboard. Each key lights up while it is held and stays marked as tested afterwards, so at the end every key you never marked is one you have not pressed yet or one that does not work. The Reset button clears the marks.
Why keys seem to be captured
While the keyboard area has focus, the page keeps the browser from acting on keys such as Tab, F5, F3 or the Windows menu key, otherwise you could not test them. Outside the keyboard area nothing is captured, so Tab, F5 and every other shortcut work normally on the rest of the page. To leave the test area press Escape twice quickly, or click anywhere outside the keyboard. A few system combinations, like Ctrl+Alt+Delete or the Windows key on some systems, can never be seen by a web page.
Ghosting and rollover
Rollover is how many keys a keyboard can report at the same moment. N-key rollover (NKRO) means any number of keys. Cheap membrane keyboards often manage only two to six, and some key combinations are blocked completely, which is called ghosting. Hold down as many keys as you can with both hands. The Max at once counter shows the highest number the keyboard reported. If you pressed more keys than the counter shows, the keyboard dropped some of them. Try the combinations you use in games, such as W, A, Shift and Space together, to see if they register.
Reading the event log
The log lists each key press and release with the key value, the physical key code and the time since the previous event in milliseconds. Key codes describe the physical position of a key, so they stay the same across keyboard layouts, which is what most games use for bindings.
FAQ
Why does the Windows key or Print Screen not show up?
The operating system handles some keys before the browser sees them. If a key never lights up while the page has focus, the system is intercepting it. Keys that appear in the log but not on the picture are listed under Other keys.
How do I stop the page from capturing my keys?
Press Escape twice quickly or click outside the keyboard area. The status line above the keyboard shows whether capture is on.
What does a stuck highlighted key mean?
If a key stays lit after you let go, the page did not receive the release event. That can mean a sticking switch, or that focus moved away while the key was held. Click the keyboard and tap the key again.
How many keys at once should a good keyboard report?
Gaming keyboards advertise 6-key or full N-key rollover. For most games, six simultaneous keys is enough. If your keyboard reports fewer than four in this test, it is likely a basic membrane model.
Does the tester work for laptop keyboards?
Yes. Laptop keys are tested the same way. Keys that only exist through the Fn layer, such as brightness or volume, are often handled by the system and may not reach the browser.