Decibel meter
Press Start and allow the microphone. The page shows the sound level now, the minimum, average and maximum since you started, and a chart of the last minute.
- Live dB with min, avg, max
- Free, no sign-up
dB
Press Start to measure
Calibrate against a sound level meter
Hold your device next to a calibrated meter, play a steady sound, and adjust the offset until both show the same level. The offset is saved on this device.
| Sound | Level |
|---|---|
| Breathing, rustling leaves | 10 to 20 dB |
| Whisper, quiet library | 30 dB |
| Quiet office, fridge hum | 40 to 50 dB |
| Conversation | 60 dB |
| Busy traffic, vacuum cleaner | 70 to 80 dB |
| Lawn mower, motorbike | 90 dB |
| Concert, nightclub | 100 to 110 dB |
| Sirens up close, fireworks | 120 and above dB |
Runs in your browser. Nothing you type or open is uploaded. Free to use, no account. More audio tools
How to use it
- Press Start and allow microphone access.
- Hold the device still and point the microphone at the sound.
- Read the live level, the average and the peak. Calibrate against a real meter for better accuracy.
How the reading works
The page measures the signal from your microphone many times a second as a level in decibels relative to the loudest the microphone can record, then adds a calibration offset to estimate the sound pressure level in dB. The average is an energy average over the time you measure, which is how sound level meters report a steady noise.
Microphones in phones and laptops differ, and browsers may apply noise reduction, so treat the number as an estimate until you calibrate it. Put your device next to a calibrated meter, play a steady sound, and adjust the offset until both agree. The offset is remembered on this device. The table lists typical levels to compare with.
Private by design
Privacy
Everything runs in this page and stays on your device. The microphone signal is measured in the page and the audio itself is discarded straight away.
This page also shows Google ads, which can use cookies. Privacy and cookies explains how.
Questions
How accurate is a decibel meter on a phone?
Without calibration it can be several decibels off, because every microphone is different. With the offset matched to a real meter it is good for comparing places and spotting loud noise.
What is a safe sound level?
Long exposure above about 85 dB can damage hearing over time, and the safe time halves for every 3 dB louder. Use the meter to find loud spots, then step back or use ear protection.
Why does the reading stay low in a loud room?
Some browsers lower loud input automatically. The page asks the browser to switch that off, and it helps to keep the device close to the sound and away from wind.
Can I record the sound?
This page measures levels only. Use the online voice recorder to keep a recording.
From the same developer
- Mic to Speaker: the matching app.
