Sound Level Meter — a dB meter in your browser
Measure ambient sound level with your microphone. Nothing is recorded or uploaded.
Measurement
No audio is recorded and nothing is uploaded. Microphone data is processed only in your browser's memory and disappears when you close the tab.
Being honest: this is not a calibrated measurement. A browser cannot know your microphone's true sensitivity, and both iOS and Android apply automatic gain. The values here are a relative indicator — useful for comparing rooms or judging whether a space is uncomfortable. Official or legal measurement requires a calibrated Class 1 or 2 meter.
Why decibels are counter-intuitive
The decibel scale is logarithmic. Every 3 dB doubles the sound energy and roughly halves the safe exposure time. So 88 dB is not "a bit more than" 85 dB — it is twice as much.
For reference: normal conversation sits around 60 dB, city traffic near 80, and a concert can pass 110 — where damage is measured in minutes rather than hours.
What dBA, peak and average mean
dBA weights the measurement to match human hearing, which is less sensitive to very low and very high frequencies. It is the number most guidelines refer to.
Peak is the single loudest instant, useful for sudden impacts. Average over time is what matters for exposure. A quiet room with one door slam is not a loud room, even though its peak says otherwise.
How to measure a room properly
Hold the phone at ear height, away from your body, with nothing covering the microphone. Measure for at least a minute — noise fluctuates, and a one-second reading tells you almost nothing.
Take readings at several points. Sound levels vary considerably across a single room depending on reflections and distance from the source.
On your phone with calibration offset, measurement history and dBA weighting.