Press start and allow microphone access.
Phone and laptop microphones are not calibrated and apply their own processing, so readings are estimates (often ±10 dB). For workplace or legal measurements use a Class 1 or Class 2 sound level meter.
How it works
The meter reads raw audio from your microphone, computes the RMS level in decibels relative to digital full scale (dBFS) and adds a calibration offset to estimate sound pressure level. Echo cancellation, noise suppression and automatic gain are switched off where the browser allows.
For better accuracy, compare it with a real sound level meter or a known source and adjust the calibration slider until the readings match.
What the numbers mean
Below 40 dB is quiet, 60 dB is conversation, 85 dB is the level at which long exposure starts to risk hearing damage, and above 120 dB is painful. See the decibel scale for every level.
Frequently asked questions
Is a phone decibel meter accurate?
Not very: uncalibrated phone microphones are often off by 5–10 dB or more, especially at high levels. Use it for comparisons and rough estimates.
Is my audio recorded or uploaded?
No. The analysis runs entirely in your browser; nothing leaves your device.