How to use the microphone test
- Press Start microphone. Your browser asks whether this page may use the microphone. Choose Allow. The question appears only after you press the button.
- Speak or clap. The level meter moves with the sound, and the numbers show the level now and the loudest sound so far in decibels.
- If you have more than one microphone, such as a headset and a laptop mic, choose another one from the Microphone list and repeat the test.
- Press Stop microphone when you are done. Use Reset the loudest value to start the peak reading again.
Reading the numbers
Levels are measured against full scale. A pure tone with half the maximum amplitude has an average power level (RMS) of 0.3536 and reads about -9.0 dB, and its loudest instant is 0.5, which reads about -6.0 dB. A signal that fills the whole range reads 0 dB, and every halving of the amplitude lowers the reading by about 6 dB.
On the meter, -60 dB is empty and 0 dB is full, so the tone above fills about 85% of the bar. Speech at a comfortable distance usually lands well below the top, and a reading that sits at 0 dB or close to it means the signal is too loud and may be distorted.
What the meter shows
The page reads short slices of the live sound, computes the root mean square of the samples, which is a measure of average power, and converts it to decibels relative to full scale. The loudest value is the largest single sample seen since the test started or was reset.
Echo cancellation, noise reduction and automatic gain control are switched off for this test, so the meter shows the raw level. Video call apps usually switch those on, which can change how loud and how clean you sound there.
Privacy
The sound is analyzed in your browser and thrown away. It is not recorded, saved, sent to a server or played back, so there is no echo or feedback while you test. The microphone is requested only after you press the button.
If the meter does not move
Check that the right microphone is selected, that it is not muted by a switch on a headset cable or a key on the keyboard, and that the browser and the operating system both allow microphone access. Close other apps that use the microphone. If the meter moves only a little, move closer or raise the input volume in your system sound settings. For a camera check use the webcam test, and to test speakers or headphones try the white noise generator or text to speech.
Assumptions and limits
- Microphone access works only on secure (HTTPS) pages and in browsers that support it.
- Readings are relative to full scale in the browser, not calibrated sound pressure levels, so they cannot tell you how loud a room is in real-world decibels.
- Device names are blank until permission is granted, so unnamed microphones are numbered.
- Some devices apply their own gain or filtering before the browser sees the sound, which this page cannot switch off.
Frequently asked questions
How do I check that my microphone is working?
Press Start microphone, allow access, then speak. If the meter moves and the level numbers change, the microphone is picking up sound.
Does the microphone test record my voice?
No. The sound is measured as it arrives and discarded. Nothing is stored, played back or sent to a server.
What do the negative decibel numbers mean?
They are measured down from the loudest value the signal can hold, which is 0 dB. A reading of -20 dB is quieter than -10 dB, and -60 dB is close to silence.
Why is the meter flat even though I am talking?
The wrong microphone may be selected, it may be muted, or the browser or system may be blocking it. Pick another device from the list and check the mute and privacy settings.