How to use it
- Press the left, middle and right buttons in the test area, then the side buttons if your mouse has them.
- Double-click in the area and watch Rapid pairs (same button). Change Rapid-press interval to see how the count moves.
- Scroll the wheel in the area and read the four scroll counts.
- Move the mouse in a circle inside the lower box for two seconds and read Estimated polling rate.
Buttons and the browser
The browser reports the left, middle and right buttons, and the back and forward side buttons on mice that have them. Some mice send extra buttons under other numbers; those appear as other buttons. In some browsers the middle and side buttons start a scroll or move through the history, so this test stops those actions on its own area only.
Double-clicks and switch bounce
A double-click switch, or a mechanical switch that bounces, can register one press as two. The test counts pairs of presses of the same button that come closer together than the chosen interval. Very close pairs are the usual sign of a switch that registers one press twice, so a rising count with the 50 ms interval is worth checking.
The scroll wheel
Each wheel event adds one to the count in the direction it moves. A stepped wheel sends one event per notch. A trackpad, or a wheel with smooth scrolling, sends many smaller events. Compare counts only between the same devices.
Polling rate
The polling rate is how often the mouse reports its position to the computer. The test estimates it from the times the browser gives each move, using the median gap so that pauses do not distort the figure. Many mice report 125, 500 or 1000 times a second. A browser can show fewer, because it merges moves into one per frame.
Example: a switch that registers twice
The left button is pressed at 0 ms, 70 ms and 300 ms. The first two presses form a rapid pair 70 ms apart, which is inside the 80 ms interval. The third press comes 230 ms after the second, so it does not pair. The result shows one rapid pair.
Frequently asked questions
Does the test record my clicks or moves?
No. Presses, scrolls and mouse moves are read by your browser while this page is open. Nothing is recorded, stored or sent to our server.
My mouse's back or forward button does nothing. Why?
Some mice do not send those buttons, or the mouse software maps them to other actions. Check the button in the mouse software and try it in this area. If the browser never receives it, the test cannot show it.
Does a rapid pair always mean a broken switch?
Not always. A pair of very close presses is a warning sign rather than proof. Repeat the test with slow and quick presses, and compare with another mouse before you decide.
Why is the polling rate lower than my mouse's specification?
The browser can merge several moves into one event per screen frame, so it may report fewer moves than the mouse sends. The estimate is a guide, not a measurement from the hardware.
Does the test work on a phone or tablet?
Touch screens do not send mouse moves or wheel events in the same way, so use a computer with a mouse for the full test. A touch on the area counts as a left-button press.
Sources
- UI Events, W3C specification (MouseEvent button values)
- Pointer Events Level 3, W3C specification
- WheelEvent, MDN Web Docs
Figures and text last checked on Tuesday, November 10, 2026.