Mouse Scroll Test
Check vertical and horizontal scroll wheel input, with raw scroll amounts and a smoothness graph.
Shows how far each scroll step moves and the unit your browser measures it in. The wheel’s own physical resolution can’t be read from a web page — the amounts depend on your browser, your system and your device.
01How this test works
Input tests watch what your browser receives from your keyboard, mouse, touchscreen or stylus while the test area is in focus. Each key press, click or movement carries details like which key or button it was, where the pointer is, how hard you pressed, and precise timing.
Rate and timing tests measure the gap between events. Where your browser allows it, we read your movements in finer detail than once per frame, then show the full spread of results rather than a single number.
Events are only captured inside the test area, so your normal browser and system shortcuts keep working everywhere else on the page.
02How to use it
- Click or tap inside the test area to give it focus.
- Press keys, click buttons, scroll, or move/drag as the test instructs.
- Watch the live visualization highlight exactly what the browser received.
- For rate tests, move or click continuously so enough samples are collected.
- Use Reset to clear the state and start a fresh measurement.
03What this test covers
What it detects
- Which keys, buttons, and touch points register in this browser session
- Scroll direction and wheel deltas, double-click intervals, and movement paths
- A browser-observed estimate of event rate (for polling-rate tests)
- The maximum number of simultaneous keys or touches the browser reports
What it can’t detect
- A device’s true hardware polling rate, DPI, or input latency
- Keys and shortcuts the operating system intercepts before the browser sees them
- Whether a fault is in the device, the driver, or OS settings like key repeat and acceleration
04Troubleshooting
| Symptom | What to do |
|---|---|
| A key doesn’t register | Some media and system keys are handled by the OS and never reach the browser. Try another key or check your keyboard layout. |
| Scroll seems reversed | That’s an OS setting (natural scrolling); the test reports the direction the browser received. |
| Event rate reads low | Move continuously, keep the tab focused, and disable power saving — the browser observes events after OS processing. |
| Right-click menu appears | The context menu is only suppressed inside the dedicated test pad; use that area for button tests. |
05FAQ
Why isn’t a key registering?
Certain keys (like some media or system keys) are handled by the OS and never reach the browser. Try a different key or check your layout.
Is my typing recorded?
No. Key and pointer events are processed locally to drive the visualization and never leave your device.
Does this work offline?
Yes, input tests work offline once the page has loaded.
Why is my 1000 Hz mouse showing less?
The browser observes events after the OS and compositor, so the measured rate can be lower than the mouse’s rated polling rate.
Can I test a keyboard’s full anti-ghosting?
Only what the browser reports in this session. Some combinations are limited by the browser or OS, so this isn’t a universal hardware certification.
Do these tests work with a trackpad or touchscreen?
Yes. Pointer events cover mouse, trackpad, touch and stylus, though exposed details like pressure vary by device.
Related tests
Check every mouse button, the scroll wheel and movement, with a live visualization of what your browser receives.
Measure the interval between consecutive clicks and check against a configurable double-click threshold.
Estimate the browser-observed event rate of your mouse from movement events. Affected by browser, OS, refresh and power settings.