About the Decibel Meter
Decibel Meter uses your device's microphone to show an estimated sound level in decibels. Press Start and allow the microphone: the page shows the current level with a label such as Quiet or Loud, the lowest, average and highest values, a short history graph and an example of what that level sounds like. If you own a real sound level meter you can calibrate the estimate against it. A phone or laptop microphone is not a calibrated instrument, so use the number to compare sounds, not for official measurements. The sound is analysed in your browser and is never recorded or uploaded.
Updated October 2026
How to use the Decibel Meter
- 1Press Start and allow the microphone when your browser asks.
- 2Hold the device steady and let the number settle for a few seconds.
- 3Read the level, the label and the lowest, average and highest values.
- 4Optionally calibrate by typing the reading from a real sound level meter.
- 5Press Stop when you are done, or Reset to start the statistics again.
How the number is made
The microphone signal is measured many times a second. The tool works out its average strength, converts it to decibels relative to the loudest level the microphone can record, and adds an offset that estimates sound pressure level. Turning off echo cancellation, noise suppression and automatic gain, where the browser allows it, keeps the reading close to the real sound.
What different levels sound like
Under 30 dB is whisper-quiet. Around 45 dB is a quiet home. A normal conversation is near 60 dB, a busy restaurant or vacuum cleaner near 75, heavy traffic close to 85 and a loud club or concert above 100. At 120 dB and above, sound hurts and can damage hearing within seconds.
- 30 dB: whisper
- 60 dB: normal conversation
- 85 dB: heavy traffic, the start of hearing risk
- 110 dB: loud concert or power tool
Getting a steadier reading
Hold the device away from your body and from wind, keep your finger off the microphone hole, and measure for at least ten seconds. Compare places with the same device and the same position. Average and highest readings tell you more than a single instant.
Related audio tools
Use the Decibel Calculator for converting between dB and power or voltage ratios, and the Audio Loudness Checker to measure the loudness of a recording. To hear a test sound, generate one with the Tone Generator, and use the Noise Generator when you need steady background noise.
Protect your hearing
If the meter shows more than 85 dB for long periods, use earplugs or earmuffs, take breaks and lower headphone volume. Ringing in your ears after a loud event is a sign of damage, so see a doctor if it does not go away.
Features
- Live estimated level in dB with a descriptive label
- Lowest, average and highest readings
- Level graph for the last half minute
- Calibration against a real meter, saved in your browser
- Hearing safety note for loud levels
- Never records or uploads sound
Frequently asked questions
How accurate is a phone decibel meter?
Not very. Microphones and phone software differ, and many devices reduce loud sounds to protect the microphone. Readings can be several decibels off, and more at very loud or very quiet levels. Use it to compare sounds on the same device.
What is a decibel?
A unit that measures sound level on a logarithmic scale. Every 10 dB is roughly twice as loud to the human ear, and every 3 dB doubles the sound energy. A whisper is about 30 dB, a conversation about 60 dB and a lawn mower about 90 dB.
What level is dangerous for hearing?
Long exposure above about 85 dB can damage hearing: roughly eight hours at 85 dB, halving the time for every 3 dB more. Very loud short sounds such as fireworks or gunshots can harm at once. Wear ear protection in loud places.
Why does it ask to use the microphone?
It needs the microphone to hear the sound. The audio is measured in your browser and discarded straight away: nothing is recorded, saved or sent anywhere.
How do I calibrate it?
Measure a steady sound with a real sound level meter and with this page at the same time, type the real number and press Calibrate. The offset is saved in your browser and used from then on.
Can I measure noise for a landlord, workplace or court?
No. Official noise complaints and workplace checks need a calibrated, certified meter and a defined method. This tool is for rough, everyday comparisons.
Why do readings jump around?
Sound changes quickly, and the number is a short average. Hold the device still, keep fingers off the microphone and read the average over a longer time.
Why does it not work on my device?
The browser must allow microphone access for this site, and the page must be opened over https. If you blocked the microphone, allow it in the browser's site settings and press Start again.