Keyboard Test for Keys, Ghosting and Chatter

Ghosting occurs when pressing multiple keys simultaneously causes some keys not to register. This test shows your keyboard's N-Key Rollover (NKRO) limit — the maximum number of keys that can be pressed at the same time.

Key chatter (also called key bounce) is when a single key press registers multiple times. This is common in worn mechanical keyboards. The tester detects chatter by measuring the interval between keydown events — anything under 50ms is flagged.

Yes. Connect an external keyboard to your phone via USB OTG or Bluetooth. The visual keyboard scrolls horizontally on small screens so you can see every key that was pressed.

On the test page your keys go to the test, not to the browser. Otherwise F5 would reload the page mid-test, F1 would open help, F3, F6, F7 and F10 would pull the focus away, and the menu key would open a context menu. Ctrl and Alt shortcuts such as Ctrl+R, Ctrl+W and Alt+F4 work as usual. Win and PrtSc are taken by Windows before the browser sees them: Win opens Start and PrtSc opens the Snipping Tool, but the press still counts, and the test tells you when the window has lost focus. To send Win and Alt+Tab to the test as well, click Full screen. The button appears in browsers that support it, such as Chrome, Edge and other Chromium-based browsers; to exit, press and hold Esc.

On many laptops the top row is a media row by default: F1 mutes the sound, F5 changes the brightness, and so on. The browser then receives volume or playback keys instead of F1–F12, and the test lists them under the board. Press the top row together with Fn, or turn on Fn Lock (Fn+Esc on many laptops), and the keys arrive as F1–F12. Brightness, backlight and Wi-Fi are usually handled by the laptop itself without telling the system, so those presses never reach a browser on any website. The Fn key itself is invisible to the browser.

Most likely your keyboard follows a different standard. A layout is either ANSI (US: a one-row Enter and a long left Shift) or ISO (most of Europe: a tall Enter, an extra key beside the left Shift, and the backslash next to Enter). The Standard switch under the test picks the layout, and pressing the key beside the left Shift switches the test to ISO on its own, because ANSI has no such key. The browser reports the pressed key by its position code, so on the wrong layout a press lights up where that code sits in the other standard. Keys the layout doesn't have at all, such as media keys and Japanese or Korean extras, are listed under the board. What matters for the test is that the press registered, and registered once.

Your reaction time: from the frame on which the area turned green to the moment the browser received your key press. Almost all of it is you (typically 150–300 ms), which is why it varies from try to try; the test averages five tries. The rest is the signal's path: the monitor frame, keyboard and USB polling, and the operating system's input queue. The page's own handler isn't included, because the press time comes from the key event itself. Compare keyboards by this number only on the same computer and over many tries: they differ by a few milliseconds, while reaction varies by tens.

Yes. Click the Export button to download a text report listing all tested keys and any issues found (stuck, chatter). This can be attached to a warranty or return request.

The heat map shows which keys you press most frequently by color-coding them from cool (blue, rarely pressed) to hot (red, frequently pressed). It helps identify wear patterns, optimize key assignments, and understand your typing habits.