What does this mouse button tester actually check?
Every press and release is captured as a browser mousedown / mouseup event and stamped with event.timeStamp. The tool classifies the event by event.button so left, right, middle, and the two side buttons each get their own counter. It then computes the interval between successive presses on the same button, the hold time on each click, and a per-switch chatter score. Nothing is sent to a server. If a button never registers, the issue is either the switch, the cable, or a driver-level remap — not the browser.
Why does my right-click open a context menu instead of registering?
Browsers raise a contextmenu event on right mouse-down by default. This tool calls preventDefault on that event so the menu is suppressed inside the pad area. If you still see the menu, a browser extension is intercepting events before the page sees them, or you are clicking outside the test surface. Click directly on the mouse illustration. Outside that region the page falls back to normal browser behaviour so you can still scroll and navigate.
Are my side buttons (button 4 and 5) supposed to register?
Yes, provided the mouse exposes them as standard HID buttons rather than as keyboard macros. Browsers map them to event.button values 3 and 4 and also fire the auxclick event. If the side buttons do nothing here but work as Back/Forward in your browser, a vendor driver such as Logitech Options or Razer Synapse is rebinding them to keystrokes before the OS sees a mouse event. Disable the rebind in vendor software to test the raw switch.
What counts as chatter and why 50 ms?
Chatter is an unintended second click produced by a worn switch contact bouncing. Healthy human double-clicks land around 120–200 ms apart, and even speed clickers rarely break 80 ms on the same button. The industry QA heuristic for debounce failure is anything under 50 ms, so this tool flags those intervals in red. One or two flags during a session is suspicious; a recurring pattern on the same button is a failing switch and usually needs a swap.
Does the test work on a laptop trackpad or a touchscreen?
Partially. Trackpad taps generate synthetic mouse events so left and right register, but middle and side buttons obviously do not exist. Touchscreens fire pointer events that the pad treats as a left click; chatter detection still works but hold times are dominated by finger contact, not switch travel. For real switch diagnostics use a wired or wireless mouse. See /mouse/double-click for a focused chatter-only test, or /mouse/polling for report-rate measurement.
Will Bluetooth or 2.4 GHz affect button readings?
Wireless transport adds jitter to the timestamps, not to whether the click registers. A click either arrives or it does not, but the interval between two clicks can drift by a few milliseconds because Bluetooth aggregates HID reports into intervals of roughly 7.5 ms. For chatter detection this is fine — chatter intervals are an order of magnitude smaller than the noise floor. For sub-millisecond hold-time analysis, plug the receiver in directly and avoid USB hubs.