🔊Sound Meter

About this tool

Press Start and allow microphone access. The meter shows the current level in estimated decibels, the minimum, average and maximum since you started, and a 30-second history chart. A calibration offset lets you match the readings to a real sound level meter. Press Stop, or leave the page, to switch the microphone off.

How a browser sound meter works

The browser reports how loud the microphone signal is compared with the loudest sound it can record, in decibels relative to full scale (dBFS). A signal at one-tenth of full scale is −20 dBFS. Adding a calibration offset turns that into an estimate of sound pressure level: with the default offset of 100, −20 dBFS reads as about 80 dB. The meter turns off the echo cancellation, noise suppression and automatic gain that browsers normally apply to voice calls, because they would flatten the readings. The average is an energy average, called Leq, as on real sound meters. So 60 dB and 70 dB average to about 67 dB, not 65. Phone and laptop microphones differ by 10 dB or more and filter some frequencies, so readings are approximate. If you have access to a real sound level meter, set the offset until the two agree and the readings become far more useful. For context, normal conversation is about 60 dB, heavy traffic about 85 dB, and long exposure above about 85 dB can damage hearing. Honest limits: this is not a certified instrument, so do not use it for legal, workplace or noise-complaint measurements. Audio is analysed in your browser and is never recorded, stored or sent. The microphone test checks your mic works, the hearing test checks your hearing range and the spectrum analyzer shows frequencies. Sample rate and bit depth explained: what 44.1 kHz and 16-bit actually mean covers digital audio basics.

Frequently asked questions