Mouse Tester

Five buttons, a wheel, and a report rate

A mouse has more moving parts than people expect, and each fails differently. The left button wears out from use; the wheel encoder gets dirty and scrolls the wrong way; the side buttons stop registering; the sensor starts reporting jitter when the mouse is still.

The panel above shows each button lighting as you press it, including the side buttons that most software ignores. Move the pointer inside the pad and it tracks coordinates and estimates how often your mouse is reporting its position.

About the report rate

The figure shown is an estimate, and worth treating as rough. Browsers deliver mouse events on their own schedule, usually tied to the display refresh, so a 1,000 Hz gaming mouse will often read as something nearer 60–250 Hz here. What the number is good for is spotting a mouse reporting far less often than it should, or one dropping out intermittently.

How to use it

1. Click each button in turn — left, right, middle (press the wheel), and the two side buttons if your mouse has them.
2. Scroll the wheel both ways. The two halves of the wheel light separately, so a wheel that only scrolls one direction is obvious.
3. Move the pointer across the pad and watch the coordinates. Jumps or freezes point at a sensor or surface problem.
4. Leave the mouse completely still for a few seconds. The coordinates should not change at all. If they drift, the sensor is picking up noise.

Common uses and tips

What each symptom usually means

• A button that sometimes does not register — a worn micro-switch. Very common on the left button after a few million clicks.
• One click registering as two — the same switch failing the other way. Check it on the double-click test, where an interval under about 60 ms is almost certainly the mouse rather than your finger.
• Scrolling that jumps backwards — a dirty or worn wheel encoder. Sometimes fixed by cleaning; often not.
• The pointer drifting when the mouse is still — sensor noise, a dirty lens, or a reflective surface. Try a proper mat before blaming the mouse.
• Side buttons doing nothing — often software rather than hardware. They may need the manufacturer's driver to be mapped to anything.

Things the browser cannot show you

• Your true DPI. A web page sees pixels moved, not counts reported by the sensor, and the operating system's pointer acceleration sits in between.
• The real polling rate, for the reason above.
• Which model of mouse it is. Browsers deliberately do not expose that.

What this tool can and cannot see

Everything here runs in your browser. Nothing about your keyboard, mouse or keystrokes is sent anywhere, stored, or logged — the page has no server to send it to.

What the browser gives a web page is also limited by design. It can see that a key was pressed and which one, but not what kind of switch it uses, its firmware, or anything about the device beyond what the operating system reports. A web page cannot tell a mechanical keyboard from a membrane one.

Questions people ask

Why does my 1,000 Hz mouse show a much lower rate?

Because browsers deliver mouse events on their own schedule, usually tied to the screen refresh. The figure here is useful for spotting a mouse reporting far too slowly, not for confirming a high polling rate.

The side buttons do not light up.

Often they are not mapped to anything at the system level. Browsers report them as buttons 3 and 4, but only if the mouse or its driver sends them as such.

My pointer drifts when I am not touching the mouse.

Usually the surface rather than the sensor — glass, gloss and patterned desks all cause it. Try a mat before assuming the mouse is faulty.

Can this measure my DPI?

No. A web page only sees how far the pointer moved in screen pixels, after the operating system has applied its own acceleration.

Is my clicking recorded?

No. Everything runs in your browser.