Quick answer
A mouse that registers two clicks less than 80 ms apart from one press has a worn switch and double-clicks by itself. Click each button slowly 20 times to check.
How to use the Mouse Tester
- Move your pointer into the test area.
- Press each button: left, right, middle (wheel click) and the side buttons if your mouse has them. Each button lights up on the mouse picture and its counter goes up.
- Scroll the wheel up and down. The wheel counters should rise one step per notch.
- To check for a double-click fault, single-click a button slowly 10-20 times. If the tester flags a fault, one press produced two clicks.
- Click Reset to clear all counters.
Example
Your mouse sometimes opens files when you only meant to select them. Click the left button slowly 20 times in the test area. Normal clicks are hundreds of milliseconds apart. If the tester reports a fault such as “second click after 23 ms”, the switch is bouncing: one physical press is sending two clicks. No human can click that fast on purpose, so it's a clear sign of a worn switch.
How it works
Each time you press a button, your browser receives a mousedown event that says which button was pressed (0 = left, 1 = middle, 2 = right, 3 = back, 4 = forward). The tester counts these events and measures the time between consecutive presses of the same button.
A real person can't press and release a button twice in less than about 80 milliseconds. When two presses of the same button arrive closer together than that, the tester flags them as a hardware fault. This usually happens when the tiny metal spring inside the switch wears out and “bounces”.
The test area blocks the right-click menu, middle-click auto-scroll and back/forward navigation, so you can test every button without leaving the page.
What to do when your mouse misbehaves
- Double-clicking fault on a mouse under warranty: run this test, take a screenshot of the fault message and include it in your warranty claim.
- Pointer jumps or stutters: that's usually the sensor, not the buttons. Clean the sensor window and try a plain, non-glossy mousepad.
- Right-click doesn't work in one program only: if it works here, the program has remapped it. Check that program's settings.
- Side buttons go back in the browser by accident: mouse software (such as Logitech G Hub or Razer Synapse) lets you reassign or disable them.
- Wheel scrolls in the wrong direction: if the tester shows the opposite counter rising, the wheel encoder is dirty. If the counters are right, check “natural scrolling” in your system settings.
Frequently asked questions
Why does my mouse double-click when I click once?
The most common cause is a worn switch whose contact bounces, sending two signals for one press. Cleaning sometimes helps, but usually the switch or the mouse needs replacing. Also check that Windows or macOS double-click speed and any mouse software macros aren't causing it.
My side buttons don't show up. What's wrong?
Some mice send side buttons only after their driver software is installed, and some browsers don't report extra buttons. If the buttons work in other programs, the mouse is fine.
The scroll wheel jumps up when I scroll down. Is that a fault?
Yes. If the wrong-direction counter goes up while you scroll one way, the scroll encoder is dirty or worn. Blowing compressed air into the wheel gap can fix it.
Does this work with a touchpad?
Yes. Tapping and two-finger scrolling are detected. Touchpads may not have a middle button or side buttons.
Is the test the same as a click speed test?
No. This page checks that your mouse hardware works correctly. To measure how fast you can click, use our click speed test.