How to use the decibel meter
- Tap Start measuring. Allow microphone access when your browser asks. The page only analyzes loudness and never stores audio.
- Hold the phone steady. Keep the microphone about 30 cm from the noise source, pointing at it, and avoid covering the mic with your hand or case.
- Read the level and graph. The big number is the current level. The graph shows the last 25 seconds, and the stats keep minimum, average and maximum.
- Calibrate if you have a reference. Enter the reading from a known sound level meter and tap Calibrate while measuring the same sound.
What is a decibel?
A decibel (dB) is a logarithmic unit for sound level. Because it is logarithmic, a 10 dB increase sounds roughly twice as loud, and a 3 dB increase doubles the sound energy. Quiet rooms sit near 30 dB, normal conversation around 60 dB, and sounds above 85 dB can damage hearing over time.
How accurate is a phone decibel meter?
Phone microphones are built for voice, with automatic filtering and limited range, so a browser meter is a useful estimate, not a certified instrument. Most phones top out around 90–110 dB, and results shift between models. This tool turns off automatic gain, echo cancellation and noise suppression where the browser allows, which keeps the reading closer to the real sound. Use the calibration slider against a reference to improve accuracy.
dB vs. dB(A)
Professional meters use A-weighting, which mimics how human ears respond to different frequencies. This tool shows an unweighted level, so low-frequency rumble can read higher than an A-weighted meter would show.
Common uses
People use a sound meter to compare how noisy two rooms are, check a neighbor or appliance, find a quiet spot to work, or see how loud their headphones are. If the mic itself seems quiet or distorted, run the microphone test. To check the other side of audio, try the speaker test.
Frequently asked questions
Open this page, tap Start measuring, allow microphone access and hold the phone near the sound. The live number shows the approximate level in dB.
It gives a good relative reading and a rough absolute one. For legal or workplace measurements use a certified sound level meter. You can improve accuracy by calibrating against a known reference.
Prolonged exposure above about 85 dB can damage hearing. Louder sounds shorten the safe time quickly, and very loud sounds such as 110 dB can cause harm in minutes.
Rooms are never perfectly silent, and the microphone has its own electrical noise. Values around 25–40 dB in a quiet room are normal for this kind of meter.
Check that your browser has permission to use the microphone for this site, that no other app is holding it, and that the page is opened over HTTPS.
No. Sound is analyzed live in your browser to calculate loudness, and nothing is recorded, saved or sent anywhere.