What this test checks
- Signal. Whether the selected input delivers anything at all, and which device the browser is really listening to.
- Level. How loud you arrive, in dBFS, with a peak-hold marker and a clip counter.
- Noise floor. What the mic picks up when you say nothing: fan, hiss, hum, the room.
- Format. Sample rate, channel count, and whether echo cancellation, noise suppression or auto gain control are altering the signal.
- Sound. A 5-second recording, played back to you, because a meter cannot tell you that you sound muffled.
How to read the meter
The scale is dBFS, decibels below full scale. 0 is the loudest value a digital signal can hold; everything real sits below it, so every reading is negative. The bar follows the short-term level, the thin marker holds the latest peak.
| Reading | Meaning |
|---|---|
| −∞, flat line | No signal. Muted, switched off, or the wrong input. |
| below −42 dBFS | Too quiet. Speech will come out noisy once it is amplified. |
| peaks −12 to −6 dBFS | Where speech belongs. Loud enough, with headroom to spare. |
| 0 dBFS | Clipping. The tops of the wave are cut off and the sound distorts. |
For the noise floor, stay silent for a few seconds. Below −60 dBFS is a quiet setup. Around −50 dBFS you will hear a fan or hiss behind your voice. Above −40 dBFS the noise competes with you — move the mic closer rather than turning it up, because gain raises voice and noise together. Read it with the processing switches off: noise suppression hides exactly the noise you are trying to measure.
If the meter does not move
- Muted in the operating system. Check the input volume in the system sound settings, the mute switch on the headset cable, and the microphone key on the keyboard. A muted mic reads as a flat line, not as an error.
- Wrong input selected. Laptops with a webcam, a dock and a headset can offer four microphones. Pick each one in the Input list and tap the mic you mean — the one that jumps is the one in use.
- Browser permission. If you once chose Block, the browser stops asking. Open the site settings from the icon next to the address bar, set Microphone to Allow, and reload.
- System permission. Windows and macOS each have their own switch under Privacy & security → Microphone. If the browser is off in that list, every site gets silence or a refusal.
- Bluetooth headset profile. A headset whose mic is in use falls back to call quality: mono, 8 or 16 kHz. That is the standard, not a fault. If the headset does not appear at all, reconnect it and check that it is paired as a headset and not only as headphones.
- In use elsewhere. On some systems a call or recording app holds the microphone exclusively. Quit it and press Start again.
Nothing leaves this device
The test never uploads audio and has nowhere to upload it to: the analysis runs in this tab, the recording is held in memory, and nothing is written to storage. The microphone opens only when you press Start and closes when you press Stop or leave the page. The full statement is in the privacy policy.
Checking a used phone or laptop before you buy it? The microphone is one part of the routine; the phone screen test covers the display and touch layer.