How to use this tool
- 1Tap 'Start measuring' and allow microphone access.
- 2Hold the phone toward the sound source and read the live dB value.
- 3Watch the color bar and the peak reading to compare quiet and loud moments.
- 4Tap 'Stop' when finished. Nothing is recorded.
About this test
This tool reads your microphone through the Web Audio API and converts the signal into an approximate decibel value, from a quiet room around 30 to 40 dB up to loud environments above 85 dB, where prolonged exposure can harm hearing.
Phone microphones are not calibrated and each model differs, so treat the number as a relative indicator for comparison rather than a certified measurement. It is ideal for checking whether a room, fan or appliance is louder than usual.
Privacy: this tool runs entirely in your browser. No image, audio or device data is recorded or sent to any server.
Frequently asked questions
How accurate is a phone decibel meter?
It is good for relative comparisons but not certified. Uncalibrated phone mics can differ by several decibels from a professional meter, and most cannot capture very loud sounds accurately.
Is my audio recorded?
No. The sound is analyzed live in your browser and never saved or uploaded.