Keyboard & Mouse Tester
Press keys and click mouse buttons to see them light up on a visual layout. Test every key, button, and scroll wheel on new or mechanical hardware.
Runs in your browser. No data leaves your device.
Frequently Asked Questions
How does the Keyboard & Mouse Tester work?
The tool listens for keydown, keyup, mousedown, mouseup, and wheel events on the document. Each event's KeyboardEvent.code or MouseEvent.button is mapped to the corresponding key or button on the on-screen SVG layout. Active keys turn blue (via CSS class toggle on keydown) and green on release (keyup), using a Set to track which keys have been tested. The mouse panel tracks five buttons plus scroll direction using the same highlight pattern.
Does it work with any keyboard layout?
The tester detects physical key positions using the browser KeyboardEvent.code property, so it works regardless of your language or layout setting. The on-screen layout shows a standard ANSI mapping.
Can it test mouse side buttons and scroll wheel?
Yes. The visual mouse shows left, right, middle, back, and forward buttons plus scroll up and scroll down. Not all mice have side buttons, so your total may vary.
Why do some keys not register?
Certain keys like Print Screen or the Fn key are intercepted by your operating system or keyboard firmware before the browser can detect them. This is a hardware or system-level limitation.