Sound level meter
How loud is it in here?
Measures through your microphone. The sound stays on this device: nothing is recorded or sent.
Right now
Tap Start listening, then hold the phone out in the open.
Safe time appears once it has heard a few seconds.
NIOSH guidance: 85 dBA for 8 hours, half as long for every 3 dB louder.
History
- Average Leq
- –
- Loudest
- –
- Quietest
- –
- Peak
- –
- Measured
- 0:00
Snapshot
Calibrate offset 100.0 dB
Phone and laptop mics aren't calibrated, so this reads as an estimate. If you know the true level, match it here. The setting stays on this device.
How it measures, and how close it is
- A-weighting turns the bass down the way your ears do, so a 100 Hz hum reads about 19 dB lower than a 1 kHz tone of the same energy. It's the "dBA" every noise guideline uses.
- Fast follows the sound with a 125 ms response, Slow with 1 second. Slow is steadier for a room; Fast catches claps and shouts.
- Leq is the energy average since you started: one number for "how loud was it, overall". Safe time comes from it.
- Peak is the single highest instant, unweighted.
- The mic's own voice processing is switched off, but some browsers and phones still adjust the signal, and most phone mics flatten out somewhere around 95 to 110 dB. Expect a few dB either way; calibrate for a closer reading.
- Hold the phone out at arm's length with the bottom mic uncovered. A pocket or a palm takes off 10 dB or more.
- Safe times follow the NIOSH recommended limit (85 dBA for 8 hours, halved for every 3 dB more) as general guidance, not a medical opinion.