Every sound tool on Sound dB Meter is free, works in your browser on phone or computer, and needs no app or sign-up. Tools that use your microphone process the sound on your device: nothing is recorded or uploaded. Pick a tool below by what you want to do, or use the table further down to find the right one for your task.
Measure Sound
- Sound Decibel Meter
Live dB(A), dB(C) and dB(Z) with average, maximum and peak, CSV export and a report image.
- Noise Monitor & Logger
Log noise for hours, even in a background tab, with events over your limit.
- Background Noise Test
Is your room quiet enough to record, sleep or study? Checks hum too.
- Classroom Noise Monitor
A full-screen traffic light that shows the class when it gets too loud.
- Microphone Test
Check your mic works, see its level in dBFS and hear a recording.
Analyze Audio
- Frequency Analyzer
Live spectrum and spectrogram from your mic, or analyse an audio file.
- Audio Loudness Meter
Integrated LUFS, true peak and loudness range for Spotify, YouTube and podcasts.
- Volume Level Comparator
How much louder is one level than another, in loudness, energy and pressure.
Generate Sound and Test Your Hearing
- Tone Generator
Sine, square and other tones from 1 Hz to 22 kHz, sweeps, noise and left/right tests.
- Online Hearing Test
Check each ear with headphones and find your hearing age.
Calculate and Convert
- Decibel Calculator
Add and average decibels, subtract background noise, distance and ratios.
- SPL Converter
dB SPL to pascals and back, sound intensity and microphone sensitivity.
- Noise Exposure Calculator
Daily noise dose under NIOSH, OSHA and EU rules, with hearing protection.
- Audio Wavelength Calculator
Wavelength of any frequency from the speed of sound.
Reference Charts
- Decibel Chart
How loud everyday sounds are, with safe listening times for each level.
- Safe Noise Levels Chart
How long each noise level is safe, from 70 to 140 dB.
Which Tool Do I Need?
| I want to… | Use |
|---|---|
| Check how loud it is right now | Sound Decibel Meter |
| Prove a neighbour or venue is too loud over time | Noise Monitor & Logger |
| Know if my room is quiet enough for recording or sleep | Background Noise Test |
| Keep a class at a sensible volume | Classroom Noise Monitor |
| Find which frequency a hum or whine is at | Frequency Analyzer |
| Check my song or podcast for Spotify or YouTube | Audio Loudness Meter |
| Play a test tone or check my speakers and headphones | Tone Generator |
| Check my hearing | Online Hearing Test |
| Work out how long a noise level is safe | Noise Exposure Calculator |
| Add two noise sources or convert dB to pascals | Decibel Calculator or SPL Converter |
Tips for Better Results
- Allow microphone access when asked, and close other apps that use the microphone, such as video calls.
- Hold the phone or laptop where your ears are, not in a pocket or against a table.
- Turn off voice isolation and noise suppression in your device settings, since they lower the measured level.
- Measure for at least 30 seconds and use the average, because most noise changes from moment to moment.
- Use headphones for the hearing test and the tone generator, and start with the volume low.
How Accurate Are Online Sound Tools?
Browser tools use your device’s microphone and speakers, so accuracy depends on the hardware. Phones and laptops typically read within a few decibels of a sound level meter in the everyday range of about 40 to 100 dB once calibrated, which is enough for most home, school and hobby uses, but not for legal measurements. Learn more in online decibel meter accuracy, see how we check our tools in the testing methodology, and read how the tools work.
Guides to Get Started
- How to measure decibels: where to hold the device and which setting to use.
- Calibrate your microphone: make phone readings match a real meter.
- What is a decibel? The logarithmic scale explained simply.
Frequently Asked Questions
Are these sound tools really free?
Yes. Every tool is free, with no sign-up, no download and no limit on use.
Do the tools record or upload my audio?
No. Microphone tools process sound in your browser in real time. Nothing is recorded unless you choose a recording feature, and even then the file stays on your device.
Do the tools work on iPhone and Android?
Yes, in any modern browser such as Safari, Chrome, Edge or Firefox. Microphone tools need permission and an HTTPS connection, which this site uses.