I built NoiseLab because I wanted a sound level meter that uses the standard weightings and measures, and says so when it cannot be sure. It gives you the number and tells you in plain words what it means and how long you can stay.
It reads LAeq over the whole session, plus Lmax, Lmin, peak, L10, L50 and L90. A, C or Z weighting, Fast or Slow, with the weighting curves from IEC 61672.
When you stop, you get a verdict: a headline, what I would do about it, and plain-word findings on level, low frequencies (C minus A), exposure, peaks and steadiness. Exposure is the hours you can stay before the 85 dB(A) upper action value (over 8 hours, 3 dB exchange rate, EU 2003/10/EC). A timeline shows the level per second, with lines at 70 and 85 dB.
A phone microphone is not a measurement microphone. Until you calibrate, the app says so, and the number can be about 5 dB off. Differences between measurements still hold; only the absolute level is uncertain. Hold it next to a reference meter, type what that one reads, and the offset stays with this phone. Nothing is recorded.
NoiseLab can hand a reading to the other labs, on your phone, on a tap and with nothing uploaded. Send a full-room level to RoomLab to see how loud a space gets when it is in use, next to its acoustics, or send your noise floor to SkillLab so an ear-training result is read against the room you are in.
All of that is free, plus your last 200 measurements, a compare that gives the dB difference, and your first PDF report. Pro is a one-time purchase, for when the number has to leave your phone: unlimited PDF reports with a statistics table and an octave-band spectrum from 31.5 Hz to 8 kHz, every reading of two saved sessions side by side, your logo on the report, and CSV or JSON export.
NoiseLab is one of seven small labs by AudioLab.tools, each made to do one job well: RoomLab (room acoustics, RT60), NoiseLab (sound level meter), MicLab (mic check), LevelLab (LUFS loudness meter), SignalLab (tone generator), TuneLab (chromatic tuner) and SkillLab (ear training). They share one look, and some hand their results to each other.
No ads. No account. Your audio never leaves your phone. Anonymous usage stats are off by default.
Questions or a bug: hello@audiolab.tools
Sound level meter in dB: LAeq, exposure hours, calibration against a reference.