In short: SoundDBMeter.com is a free sound decibel meter plus a set of browser-based sound tools and plain-English guides to decibels, noise exposure and measurement. Everything runs in your browser, with no app and no account, and the site is independently run by Addito.
The site started from a question people ask every day: how loud is it here? The meter on the homepage answers it with your device’s microphone. The rest of the site explains what the number means, how it compares with everyday sounds, when it can be trusted and when it cannot.
What SoundDBMeter.com is
SoundDBMeter.com is an educational website about sound levels. It pairs practical tools with guides, so you see more than a changing number: you learn what affects the reading, how to measure more consistently and when a professional meter is needed. A decibel reading is most useful when it is measured carefully and read in context.
It is written for people who want to understand everyday sound: home users checking room noise, apartment residents comparing levels, students learning about decibels, musicians and podcasters checking background noise, teachers and office workers, parents looking at nursery levels, and anyone curious about how loud their surroundings are.
Our tools
Every tool is free, runs in the browser and works on phones, tablets and computers. They are grouped below by the job they do; the full list is on the sound tools page.
Measure sound with your microphone
- Noise Monitor & Decibel Logger
Logs one value per second, marks loud events and reports L10, L90 and time over your limit.
- Background Noise Test
A timed test that says whether a room is quiet enough for sleep, recording, class or calls, and flags 50/60 Hz hum.
- Classroom Noise Monitor
A traffic-light display for teachers, with presets and adjustable limits.
- Microphone Test
Checks input level, clipping and device settings, with an optional short recording kept on your device.
- Frequency Analyzer
Live spectrum and spectrogram from the microphone or an audio file.
Calculate, convert and compare
- Decibel Calculator
Add or subtract levels, energy averages, distance, ratios, dBm and sones.
- SPL Converter
dB SPL to pascals and back, plus microphone sensitivity.
- Volume Level Comparator
How much louder one level sounds than another.
- Noise Exposure Calculator
Daily noise dose against NIOSH and OSHA limits, with hearing protection.
- Audio Loudness Meter
Integrated LUFS, loudness range and true peak for an audio file.
Listen and look up
- Tone Generator
Sine, square, sweep, beep and noise, with WAV download.
- Online Hearing Test
A relative left/right check across pitches with headphones. Not a clinical test.
- Decibel Chart
23 everyday sounds with safe listening times and a level checker.
Who runs SoundDBMeter.com
SoundDBMeter.com is independently run by Addito, who builds and tests the tools and writes and reviews the guides. The site is not a laboratory, medical provider, government agency, workplace-safety authority or standards body, and it does not present itself as one. Its value comes from free tools, careful explanations and clear limits. Addito’s role and the pages they work on are described on the author page.
How we build and test the tools
The tools use the Web Audio API built into modern browsers. A microphone tool turns the audio samples into a level in dBFS, applies the frequency weighting and time response you choose, and adds an offset to give an estimated dB value. The step-by-step version is on how the sound meter works.
Before a tool version is released it goes through a written QA run in a WordPress test install with Microsoft Edge, using generated reference signals played through a simulated microphone, so the correct answer is known in advance. The current QA reports for 15 tools list 393 passed checks, 0 failed checks and 78 items marked as not tested. A few examples:
- The meter read a 1 kHz test tone as 76.9 dB(A), against an expected 77.0 dB(A).
- Its A- and C-weighting filters were checked against the IEC 61672 table from 31.5 Hz to 16 kHz and stayed within ±0.3 dB up to 4 kHz.
- The loudness meter’s engine matched the EBU Tech 3341 and 3342 reference cases, for example −22.99 LUFS for a −23 LUFS test signal.
- Calculator results were compared with hand-worked values, such as 60 dB + 60 dB = 63.0 dB.
We also publish what was not tested. Safari on Mac and iPhone, Firefox and Chrome on a physical Android phone were not available for these runs, and synthetic signals are not the same as a real room. The full method is on the testing methodology page.
Our editorial standards
Guides are written in plain English and checked against primary sources. Exposure times follow the NIOSH and OSHA formulas, frequency and time weighting follow IEC 61672, and loudness follows EBU R128 and ITU-R BS.1770. Everyday examples are given as ranges, because real levels depend on distance, room and source. Pages are updated when a tool changes, a source changes or a reader reports an error. Read the editorial policy and the list of references and sources.
Honest about accuracy
A phone or laptop microphone is not a Class 1 or Class 2 sound level meter. Devices differ in sensitivity, some apply automatic gain or noise suppression that a browser cannot switch off, and the reading starts from a nominal offset. That is why every reading on this site is called an estimate.
Readings are most useful for comparing similar conditions with the same device, spotting changes over time and learning how levels behave. To get closer to a real value, calibrate your microphone against a reference meter. The full picture is in how accurate an online decibel meter is.
Do not use a browser reading as the only basis for workplace compliance, legal complaints, building or rental disputes, medical decisions or product certification. For those, use a calibrated professional meter and qualified advice. Our disclaimer sets out the limits.
Privacy by design
Microphone access starts only when you press Start on a tool that needs it. The audio is analysed in your browser; it is not uploaded to our server and no external audio-analysis service is used. The microphone test can make a short recording if you ask it to, and that recording stays in the page on your device. Settings such as your calibration offset, limits and recent sessions are kept in your browser’s local storage.
You do not need an account. The site uses Google Analytics 4 to understand general usage. It does not currently show ads or use affiliate links. Details are in the privacy policy.
Contact and corrections
Found an error, a broken tool or a reading that looks wrong? Tell us. Corrections, accuracy reports with your device and browser, bug reports, accessibility problems and privacy requests are all welcome. The email addresses and what to include are on the contact page.