Keyboard Test and Mouse Test – Keys, Clicks and Polling Rate
Check that every key, mouse button and the scroll wheel work, then measure your mouse polling rate, key press length and keyboard repeat speed, right in the browser.
Click the test box and press each key: it lights up while pressed and turns green once it works. On the mouse tab, click, double-click, right-click and scroll to see each counter go up. Keys or buttons that never react, or that count twice from one press, are faulty.
How to use the Keyboard and Mouse Test
- Keyboard test: click “Click here, then press any key” and press every key. The last key, its code and keyCode are shown, with a count of tested keys. Press Esc twice or click outside to stop.
- Mouse test: click, double-click, right-click, middle-click and scroll inside the box. Side buttons (back/forward) are counted too, along with the gap between clicks.
- Polling rate & latency: move the mouse quickly in circles in the first box to see current, average and maximum Hz. In the second box, tap keys or hold one down to measure press length, repeat delay and repeat rate.
No software to install. Key presses are only captured while the test box is active.
What the keyboard test checks
The on-screen keyboard is a full-size US (ANSI) layout with the main block, arrow and navigation keys and the numpad. Keys are detected by their physical position, so the test also works with other layouts such as UK or AZERTY, even if a label differs. Use it to find dead keys after a spill, keys that “ghost” when several are pressed together, or a numpad that only works with Num Lock on.
Some keys never reach a web page: Fn is handled inside the keyboard itself, and the operating system may keep Print Screen or the Windows key for its own shortcuts.
Mouse test: double clicks and scroll
A worn switch often sends two clicks for one press. If the double-click counter goes up when you click once, or the “fastest click gap” shows a few milliseconds, the switch is bouncing. The scroll counters show whether the wheel skips or scrolls the wrong way.
Polling rate explained
| Polling rate | Report every | Typical device |
|---|---|---|
| 125 Hz | 8 ms | Basic office mouse |
| 500 Hz | 2 ms | Mid-range mouse |
| 1000 Hz | 1 ms | Most gaming mice |
| 4000–8000 Hz | 0.25–0.125 ms | High-end gaming mice |
The polling rate is how often the mouse reports its position to the computer. Browsers can group mouse events, so the result is an estimate: move fast and steadily, and look at the maximum value. If you get about half of what your mouse software says, try another browser or a USB port directly on the computer.
Keyboard latency and repeat
Repeat delay is the pause before a held key starts repeating, and repeat rate is how many characters per second follow. Both are set in Windows, macOS or Linux keyboard settings. Event delay shows how long the page took to handle a key event; it measures the browser, not the full keyboard-to-screen lag.
Related tools: CPS Test, Typing Speed Test and Mic Test.
Frequently asked questions
How do I test if all my keyboard keys work?
Click the keyboard box and press every key once. Each working key turns green. Any key that stays grey did not send a signal.
Why does my mouse double-click when I click once?
Usually a worn switch that “bounces”. Check the double-click counter here; cleaning, a new switch or a warranty claim are the usual fixes.
How do I check my mouse polling rate?
Open the polling rate tab and move the mouse quickly in circles. The maximum Hz should be close to 125, 500, 1000 Hz or higher, depending on your mouse.
Why does the Fn key not light up?
Fn is handled inside the keyboard and is not sent to the computer, so no website or app can detect it.
Does the test work on a laptop or Mac?
Yes. It works with built-in, USB and Bluetooth keyboards and mice. A Mac’s Command key appears on the Win key position.
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