Sound Meter: Decibel & Noise

Sound Meter is a fast, private decibel meter and noise level meter for your phone. See how loud it really is in dB, log noise for hours, export a PDF report and measure your room's echo (RT60).

WHY PEOPLE CHOOSE SOUND METER
• Your audio is analysed in memory on the phone and is never stored as a recording
• Uses the raw microphone signal where your phone allows it, so automatic gain control does not flatten your readings
• Proper sound level meter maths: A, C and Z frequency weighting with Fast and Slow response
• One app for quick checks, long noise logs and room acoustics

SOUND LEVEL METER (dB METER)
• Live decibel reading on a colour-coded scale: green, amber, red
• A-weighting (dBA), C-weighting (dBC) and Z (flat) weighting
• Fast (125 ms) and Slow (1 s) time response
• LEQ, MAX, MIN, peak and statistical levels L10, L50 and L90
• Last-60-seconds graph with 70 dB and 85 dB guide lines
• Overload warning when the microphone clips, so you know when a reading cannot be trusted

NOISE LOG
• Record LAeq, LAFmax and LAFmin over minutes or hours
• Keeps logging with the screen off
• Per-second chart, session history and full details
• Export a PDF report or a CSV file for your records

ROOM ACOUSTICS (RT60)
• Measure reverberation time with one hand clap or a balloon pop
• Octave bands from 125 Hz to 4 kHz, T20 and T30, with a clear reason whenever a band is too noisy to measure
• Handy for home studios, podcast and video rooms, home cinema, classrooms and offices

CALIBRATION
• Match your phone to a reference meter or to a 94 dB / 114 dB acoustic calibrator
• Fine-tune in 0.1 dB steps; your calibration is remembered for your phone model

USE IT FOR
• A noisy neighbour, a loud appliance, a fan or an air conditioner
• A documented noise record for a landlord, employer or council
• Checking how loud a workplace, classroom, restaurant or event really is
• Finding the quietest room for sleep or work
• Typical levels: whisper about 30 dB, quiet room 40 dB, conversation 60 dB, busy street 80 dB, power tools 100 dB, concert 110 dB

YOUR AUDIO STAYS ON YOUR PHONE
The microphone is used only to measure levels. Audio is analysed in memory as it arrives and is never saved as a recording.

GOOD TO KNOW
Phone microphones vary and are limited at very high levels, so calibrate for best results. Sound Meter is not certified to IEC 61672 Class 1 or Class 2 and is not a replacement for a calibrated meter for legal, regulatory or occupational-safety use.

Questions or ideas? Use Feedback in the app menu. If Sound Meter helps you, a rating on Google Play means a lot.