How the test works
Press Start and everything you do with the mouse inside the dark panel is captured: the left, middle and right buttons, the two side buttons, the wheel in both directions, double-clicks and movement. The picture shows a mouse from above with each button lit while it is held and tinted once it has been pressed, and the wheel pill lights its upper or lower half as you roll it. The browser's own reactions are held back inside the panel, so a right-click opens no menu, a middle-click starts no autoscroll and the side buttons do not navigate.
The readout in the corner shows one of three things, chosen with the control below the panel. Buttons counts how many of the five buttons have registered and how many bounces were caught. Double-click shows the time between your last two left clicks and whether the operating system accepted them as a double-click. Polling rate shows the estimated report rate of the mouse in hertz, with the nearest standard setting next to it, once the mouse has moved for a few seconds. All three are measured all the time; the control only picks what is displayed.
A bounce is counted when a button is pressed again less than 40 milliseconds after it was released. Fingers cannot do that, worn switches do it all the time, and it is the cause of the "my mouse double-clicks by itself" complaint. The double-click timer measures the interval between two presses of the left button up to one second apart and keeps the fastest one.
What the result means
The result is the number of buttons that registered, out of five. The context line adds the bounces caught, the fastest double-click interval and the estimated polling rate.
- 5 buttons, 0 bounces. Every switch works and none chatters. The mouse is fine.
- Fewer than 5 buttons. Either the mouse has fewer buttons, which is normal for a simple three-button mouse, or a button is dead. A side button that does nothing on a mouse that has one is a failed switch or a driver utility that has remapped it.
- Bounces greater than 0 on a button you clicked slowly. The switch is chattering. Expect selected text to drop, drags to release early and files to open when you meant to select them.
- Double-click above 500 milliseconds and "OS double-click: no". You are slower than the operating system's double-click window. Lower the double-click speed in the mouse settings rather than blame the mouse.
- Polling rate near 125 Hz on a gaming mouse. The mouse is in a power-saving mode or its driver setting is at the default. Set it to 500 or 1000 Hz in the vendor software; higher only helps if the display is fast enough to show it.
What to do about a dead or bouncing button
Try another USB port and, for a wireless mouse, fresh batteries or a charge and a receiver plugged directly into the computer rather than a hub. Remove any mouse utility that remaps buttons and test again. For a bouncing switch, a burst of contact cleaner through the gap next to the button works for weeks to months; replacing the switch is the permanent fix and a common repair for popular gaming mice. Uninstalling and reinstalling the mouse driver fixes buttons that stopped working after an update.
When to return or claim the warranty
A new mouse with a dead button or a switch that bounces is defective; exchange it within the return window. For a warranty claim, screenshot the panel with the buttons readout showing the bounce count, and describe the symptom as unintended double-clicks; manufacturers know it well and several have extended warranties for exactly this fault. Switch wear from normal use inside the warranty period is covered; a mouse that stopped working after a drink was spilled on it is not.
Frequently asked questions
What is a bounce and why does the test count it?
A bounce is a second press of the same button within 40 milliseconds of the release, faster than any finger can click. It is the signature of a worn micro-switch: the contact chatters and the computer sees a double-click where you made one. Even the fastest deliberate clicking peaks around fifteen to twenty clicks per second, fifty milliseconds and more between presses, so anything under forty is the switch, not you.
My mouse registers a double-click when I click once. Can this be fixed?
Sometimes. Spraying contact cleaner into the switch helps for a while, and on many mice the switch can be soldered in for a few euros if you are comfortable with an iron. Operating systems also offer a double-click speed setting, which only hides the symptom. A mouse under warranty with confirmed bounces should be exchanged; it will not get better on its own.
How accurate is the polling rate?
It is an estimate from the timing of pointer samples the browser hands over while the mouse moves. Chrome, Edge and Firefox pass on the raw samples and the estimate lands near the true rate, usually 125, 500 or 1000 Hz. Safari coalesces movement to one sample per frame, so there the readout is capped at the display's refresh rate and marked as browser-limited. Keep the mouse moving in wide circles for a few seconds before reading the number.
Why do the back and forward buttons sometimes navigate anyway?
The panel asks the browser not to act on the side buttons, and Chrome and Edge honour that. Firefox on Windows and some mouse driver utilities handle those buttons as system commands before the page sees them, and then the browser goes back a page. If that happens the button works; the page simply could not stop the shortcut.
Does the test work with a trackpad or a touch screen?
A trackpad click counts as the left button, a two-finger click as the right button, and a two-finger swipe as the wheel. On a touch screen every tap counts as the left button and there is no polling rate to measure. The test is meant for a mouse; a trackpad has no switches to bounce and no polling rate to speak of.