Before a call or a recording
Check your microphone before a job interview on Zoom, a Teams meeting, a game session on Discord or a podcast recording. If the meter stays flat while you talk, the browser is getting no sound: the wrong input may be selected, the microphone may be muted with a hardware switch, or another app may be using it.
The test turns off echo cancellation, noise suppression and automatic gain, so you hear the raw signal of the microphone. Video call apps usually switch these on, which is why you may sound a little different there.
Reading the meter
Normal speech at a usual distance shows around -30 to -12 dB. If you stay near -50 dB, move closer or raise the input level in your system sound settings. If the bar turns red and the meter shows a red border, the signal is clipping and will sound distorted; lower the level or move back a little.