About this mic test
Press Start, allow microphone access, and speak: the meter moves if the browser hears you, and the readout names the device it opened, which catches the classic failure of the wrong input being selected. The audio graph runs entirely in the page. Nothing is recorded, nothing is transmitted, and stopping the test releases the microphone immediately. A healthy mic pushes the bar into the yellow on normal speech; a dead bar with permission granted means a muted mic, a wrong default device, or another app holding it exclusively.