Sound Level Meter (Decibel Meter)
Measure noise levels with your microphone — live decibel reading, peak, average and a history graph — with calibration and noise-exposure guidance.
How to use
- 1Press Start and allow microphone access.
- 2Hold the device still; read the level, peak and average. Use the calibration offset if you have a reference meter.
How it's calculated
The meter measures the RMS level of the microphone signal in dBFS and adds a calibration offset to estimate dB SPL. Phone and laptop mics vary, so readings are approximate (±5–10 dB) without calibration.
Frequently asked questions
How accurate is it?
Consumer mics and browser processing limit accuracy. Treat readings as estimates unless calibrated against a real sound level meter.
How loud is too loud?
Prolonged exposure above 85 dB(A) can damage hearing; at 100 dB, safe exposure is about 15 minutes per day.
Why does the level change when I talk near it?
Distance matters: sound level drops about 6 dB each time the distance doubles.