Scroll Wheel Test
Free · No installCheck both wheel directions. Keep a steady direction during each phase.
A mouse needs a computer.
Open this page on a computer and connect your mouse to test it. You can copy the link below.
A connected mouse on a touchscreen device can also work. Touch taps cannot test physical mouse buttons.
Receive 10+ events in each direction. Hold the pointer in the test area. Rotate the wheel, rather than pressing it.
Back/Forward mouse events and delivered navigation shortcuts are blocked while a test is active. A driver command that never reaches this page may still navigate; use standard side-button assignments in your mouse software for this test.
Your result
Browser observations only. Compare another port or computer before concluding there is a hardware fault.
Allow optional Google Analytics for page visits and test activity? Mouse movements and test results stay local. Privacy & choices
How to read your result
Keep your pointer in the test area and rotate the physical mouse wheel steadily in the instructed direction. First receive at least ten upward browser wheel events, then select the Down phase and receive ten downward events. One notch can produce more than one event, and event amounts can use pixels, lines or pages. The tool counts reports rather than pretending to count hardware notches. A Normal sample matches both directions; Excellent uses at least forty total events. The score is the percentage matching the instructed phases. An opposite-direction event is a suspect signal, but natural-scrolling settings, an accidental reversal, a trackpad or an encoder problem can all produce it. Check the visible direction before repeating the protocol. Pressing the wheel is middle-click and belongs in the mouse button tester. If wheel events arrive here but your application does not scroll, investigate focus, modifier keys and application settings first.
What to do if something looks wrong
- Reconnect the mouse or receiver directly to a different USB port. Bypass an unpowered hub.
- Check charge, batteries and visible cable damage. Replace a detachable cable with a compatible known-good cable.
- Disconnect the mouse before gently clearing loose dust around buttons and the wheel. Follow the maker’s cleaning instructions; do not pour liquid into it.
- Check button assignments and install updates from your operating system or mouse manufacturer. Avoid third-party driver download sites.
- Compare another application and computer. Wheel events here with no page movement elsewhere suggest an application/settings issue; missing or irregular rotation across computers makes a physical wheel problem more plausible.
Related mouse tests
Frequently asked questions
Does the scroll wheel test count physical wheel notches?
No. It counts the wheel events delivered by the browser. Mouse software and the operating system can turn a notch into different amounts and numbers of events.
Why does my wheel direction look reversed?
Natural-scrolling or other input settings can reverse reported direction. Check your system settings and follow the direction shown by the tool. Reversed direction alone does not identify a broken encoder.
Why can I scroll here but not in another app?
Receiving wheel events confirms that the browser saw input in this sample. Another app may have different focus, scrolling settings, an extension conflict or a modifier-key action. Compare that app before replacing hardware.
Is a wheel click the same as scrolling?
No. Pressing the wheel is the middle button. Rotating it generates wheel events. These use different signals and can fail independently; test both.
Sources and test limits
Methods are browser observations, not hardware certification. See the scoring formulas and limitations.
Return to Mouse Test to start another check.