Wheel event monitor
Test vertical and horizontal scrolling, inspect normalized delta values, and confirm that wheel events reach your browser.
For complete results, use a desktop or laptop with a connected mouse.
Scroll inside this area
Wheel and trackpad events are measured without scrolling the page while the pointer is over the test area.
Trackpads can produce small, high-frequency, diagonal, or momentum events. Those patterns are not evidence of a mouse fault.
Move the pointer over the test surface and scroll in short steps. Vertical direction should generally match your motion, while supported tilt wheels can also produce horizontal values. Occasional small variations are normal across devices.
Browsers report wheel movement in pixels, lines, or pages. This tester normalizes line and page input to an approximate pixel scale so values remain readable, but the number is not a physical distance or a universal sensitivity score.
Trackpads often emit smaller events, diagonal movement, and momentum after your fingers stop. Smooth-scrolling software can do the same. Those patterns should not be described as mouse wheel failure without comparison on the intended device.
Place the pointer inside the test area and scroll in both directions. Confirm that the direction label, delta Y value, event count, and activity indicator update.
Browsers, operating systems, drivers, smooth-scrolling tools, and devices use different event units and acceleration. The values are best used for comparison within the same setup.
Yes, when your tilt wheel, trackpad, or device software sends horizontal wheel events to the browser, the test reports direction and delta X.
No. Momentum and diagonal events are common trackpad behavior. Test with the intended mouse and compare another application before interpreting the pattern.
More diagnostics
Use each focused test to compare click, button, wheel, and movement behavior without uploading event data.
