This mouse test checks that every part of your mouse works. Click inside the test area to light up the left, right, middle and side buttons, spin the scroll wheel to check both directions, and double-click to test for unwanted "chatter". A live clicks-per-second (CPS) counter and cursor position are shown too.
Use it to detect a dead button, a worn switch that double-clicks on its own, an unresponsive scroll wheel, or to measure your click speed. It works with any mouse, trackpad or trackball.