Decibel Meter
Short answer
This free decibel meter uses your phone or laptop microphone to estimate how loud your room is, in decibels (dB). Press start and wait 10 seconds to get the average, the highest level and an everyday comparison. Sounds at or below 70 dB are unlikely to harm hearing. Long or repeated time at 85 dB or more can.
Press start, then allow the microphone
Adjust the reading
Phone and laptop microphones are not all the same. If you have a real sound meter, measure the same sound with both and move this reading to match.
Nothing is recorded or sent. Your browser checks the sound on this device and throws it away.
Too noisy to sleep?
BRW covers traffic, snoring and neighbours with brown, pink or white noise. It plays brown noise offline all night, with a sleep timer.
How to Use the Decibel Meter
- Press Start measuring and allow the microphone when the browser asks.
- Hold the phone where you want to know the level, for example on your pillow. Do not cover the microphone.
- Stay quiet for 10 seconds. Then the page shows your result: the average level, the highest level and the kind of sound it heard.
- Measure at the time the noise bothers you. Traffic and neighbours are often different at 11 pm and at 3 pm.
What the Numbers Mean
Decibels do not go up in a straight line. Each step of 10 dB sounds about twice as loud. So 60 dB sounds about twice as loud as 50 dB.
| Level | What it is like | What to know |
|---|---|---|
| Below 30 dB | Very quiet | Hard to measure with a phone. Many phones cannot read this low. |
| 30–40 dB | A still bedroom at night | A good level for sleep. |
| 40–55 dB | A calm home or office | The WHO recommends road traffic noise outside at night below 45 dB [2]. |
| 60–70 dB | Normal conversation | At or below 70 dB, sound is unlikely to harm hearing, even after a long time [1]. |
| 70–85 dB | Busy traffic close by | Loud. Too loud to sleep in. |
| 85 dB and more | Very loud | Long or repeated time at this level can cause hearing loss [1]. |
How Accurate Is an Online Decibel Meter?
It gives an estimate, not an exact measurement. Every phone and laptop has a different microphone, and a web page cannot know how sensitive it is. The number can be off by 10 dB or more.
It is still very useful to compare. Measure with the window open and then closed. Measure your bedroom and then the living room. Measure before and after you turn on a fan. The difference between the readings tells you a lot.
If you have a real sound meter, measure the same sound with both. Then use Adjust the reading to match. The page remembers your adjustment on this device.
Which Sound Covers Your Noise Best?
The meter also listens to the kind of sound in the room, and suggests a noise colour to cover it. The rule is the same as on our sound masking page:
Low, rumbly sound (traffic, engines, footsteps, snoring): brown noise. It is deep, so it covers deep sounds well at a low volume. See block traffic noise and block out snoring.
Voices and higher sound (talking, a TV, music through a wall): white noise or green noise. See block neighbour noise.
A mix, with nothing that stands out: pink noise. It is in the middle, between brown and white.
Covering a sound does not make it go away. It makes it stand out less, so your brain stops noticing it. Keep the covering sound low: just loud enough that the noise stops standing out, and well below 70 dB.
Is It Safe to Allow the Microphone?
Yes. The sound from the microphone is checked in your browser, on your device, and thrown away at once. Nothing is recorded, saved or sent to us or anyone else. The page keeps only one number: your adjustment, if you set one.
You can stop at any time with the Stop button. The microphone turns off when you stop or leave the page.
References
- Noise-Induced Hearing Loss. National Institute on Deafness and Other Communication Disorders (NIDCD), NIH. nidcd.nih.gov/health/noise-induced-hearing-loss
- Environmental Noise Guidelines for the European Region. World Health Organization, 2018. who.int/europe/publications/i/item/9789289053563
Frequently Asked Questions
Is this online decibel meter accurate?
It gives an estimate. Every microphone is different, and a web page cannot know how sensitive yours is, so the number can be off by 10 dB or more. It is good for comparing two places or two times. To make it closer, match it to a real sound meter with Adjust the reading.
Does the decibel meter record me?
No. The sound is checked on your device and thrown away at once. Nothing is recorded, saved or sent.
How many decibels is too loud?
Sounds at or below 70 dB are unlikely to harm hearing, even after a long time. Long or repeated time at 85 dB or more can cause hearing loss. This is the advice of the NIDCD, part of the US National Institutes of Health.
How loud is 60 decibels?
About as loud as normal conversation. The NIDCD puts normal conversation at 60 to 70 dB.
What is a good decibel level for sleep?
Quieter is better. A still bedroom at night is often about 30 to 40 dB. The WHO recommends keeping road traffic noise outside at night below 45 dB. If your room is louder, a steady covering sound at a low volume can make sudden noises stand out less.
Why does my phone show a different number from another app?
Each app and each phone handles the microphone in a different way. Without a real sound meter to compare with, no phone app is exact. Use one app and one phone when you compare readings.