Hardware diagnostic
Mouse Button Test
Press any button — it lights up while held and its counter ticks up. Right-click menus and back/forward navigation are disabled on this page so every button is safe to test.
Left
0
Middle
0
Right
0
Back (M4)
0
Forward (M5)
0
Press any mouse button — it lights up while held. A button that counts without you pressing, or fails to light while held, is faulty.
What to look for
A healthy button does three things: it lights the moment you press, stays lit exactly as long as you hold it, and adds exactly one to its counter per press. Each failure mode points at a different fault. A button that needs a hard press before it registers has a worn or dirty switch. One that flickers while you hold it steady is losing contact — the same wear that causes drag-and-drop to randomly release. A counter that jumps by two on a single press is chatter; confirm it on the double click test, which measures the timing precisely.
Side buttons (M4/M5) deserve a special check because many games bind crucial actions to them. If they don't register here at all, the cause is usually software rather than hardware: vendor drivers sometimes remap them to macros or media keys before the browser ever sees them. And if a button registers presses you never made while the mouse sits untouched, that's a failing switch or cable — worth fixing before it fires mid-game.