What Is the Mouse Tester?
A mouse tester is an all-in-one diagnostic tool that verifies every button and the scroll wheel on your mouse are working correctly. You can test your left, right, middle, back, and forward buttons — each click is captured and logged with its button label and timestamp. The scroll wheel section detects scroll direction (up or down), the delta value per scroll step, and the scroll event rate per second. Whether you are troubleshooting a sticky button, checking a new mouse before purchase, or simply curious about your hardware behavior, the mouse tester gives you instant real-time feedback without installing any software.
How It Works
The tester listens for mousedown events inside the test area, suppressing the browser context menu so right-clicks are captured rather than triggering a menu. Each mousedown event carries a button property (0 for left, 1 for middle, 2 for right) which the tool maps to a human-readable label and adds to the event log. Simultaneously, the scroll wheel section listens for wheel events and reads the deltaY property to determine scroll direction and magnitude. All events are timestamped and displayed in a unified log sorted by most recent first, giving you a clear picture of your mouse activity in chronological order.
How to Use
- Click or scroll inside the large test area on this page.
- Left-click, right-click, and middle-click to register each button.
- Scroll your mouse wheel up and down to test the scroll function.
- Watch the stats row update in real time — total clicks, per-button counts, scroll events, and scroll speed.
- The mouse button diagram highlights which button is currently being pressed.
- Review the event log for a full history of clicks and scrolls.
- Click Reset to clear all data and start a fresh session.
Tips & Information
Test All Buttons Systematically
Click each button at least five times. If any click does not register in the log, that button may be faulty. Side buttons (back and forward) are especially prone to intermittent contact issues and are worth testing separately.
Check for Double-Click Chatter
If a single physical click shows two entries in the log within milliseconds, your mouse switch may be chattering. Intervals under 80ms between clicks from a single press indicate a worn microswitch. Use our dedicated Double Click Test for more detailed chatter analysis.
Scroll Wheel Skip Detection
Scroll slowly one notch at a time and watch the delta value. A healthy scroll wheel produces a consistent delta (typically 100 to 120) with each notch. If some notches produce no event, or if the direction flips unexpectedly, the scroll encoder may be dirty or worn.
Right-Click and Middle-Click
Right-click and middle-click failures are common but easy to miss in daily use. Test them directly in this tool. If the middle-click does not register but left and right do, the middle switch inside the scroll wheel assembly may need servicing.
Try Multiple Mice
If you have a spare mouse, run this test with both to compare behavior. This quickly tells you whether an issue is specific to one mouse or relates to your browser, OS, or USB port.
Frequently Asked Questions
Why is my right-click not showing in the log?
The test suppresses the browser context menu to capture right-clicks. If right-clicks still do not appear, your mouse button may be faulty. Try in a different browser to rule out a browser extension overriding right-click behavior.
How do I test my scroll wheel?
Hover your cursor over the test area and scroll your mouse wheel up or down. Each scroll step registers an event showing the direction and delta value. If nothing appears, check that your scroll wheel moves freely and is not set to very low sensitivity in your OS settings.
What does scroll delta mean?
Scroll delta is the value the mouse sends with each wheel event, representing the magnitude of the scroll step. Standard mice typically send a delta of 100 to 120 per notch. Smooth-scrolling mice send smaller, more frequent values.
Can I test my laptop trackpad?
Yes. A laptop trackpad generates mouse events when tapped (click) and two-finger swipe (scroll). Clicks register as left-clicks by default. Two-finger scrolling produces wheel events that the tester captures.
My mouse button works everywhere but not here — why?
Some browser extensions (ad blockers, click managers) intercept mouse events. Try the test in a private or incognito window with extensions disabled. Also ensure the test area has keyboard focus by clicking once on the page.
Does the tool save my test results?
No. All data is kept in memory and cleared when you refresh or click Reset. Nothing is sent to any server. Your test session is entirely private.
What is a normal scroll events per second rate?
During fast scrolling, a standard notch-based mouse produces about 5 to 15 events per second. Smooth-scrolling mice or trackpads can produce 30 to 60 events per second. Very low rates may indicate a slow-polling USB connection.
Can I detect a double-click problem with this tool?
You can see if a single press produces multiple entries in the log. For precise double-click chatter analysis with millisecond-level intervals, use the dedicated Double Click Test on this site.