Making Browser Audio Testing Easier to Understand

We built Decibel Meter Lab because a number or a test tone is only useful when you know what it means, what to try next, and where the result has limits.

Why we built it

Why We Built Decibel Meter Lab

A browser can measure a microphone signal or play a controlled sound. The harder part is helping someone make sense of it.

We noticed that many audio tools stop at a reading, a waveform, or a tone. A decibel number can appear without explaining why another device shows something different. A microphone check can end at “working” without helping you diagnose a low or noisy input. A speaker test can play a signal and leave you wondering what a missing channel means.

Decibel Meter Lab exists to connect the test with the explanation: what the tool does, what the result suggests, what to check next, and what the browser cannot establish. We want that path to be free, available in a browser, private where microphone and file processing allow it, practical, and easy to follow.

The Problems We Wanted to Solve

Numbers without meaning.Sound-level estimates need context about device differences, gain and measurement conditions.
Binary microphone checks.Knowing that a microphone is detected is only the first step; input level and response matter too.
Signals without guidance.Speaker and headphone tests are more helpful when they explain channel checks and likely troubleshooting steps.
Technical ideas without a clear entry point.Frequency, phase, FFT, spectrum, spectrogram, bass response and calibration deserve plain explanations before deeper detail.

What We Built

Choose the test that matches your question. Each tool gives you a starting point and guidance for reading its result.

Decibel Meter

See a live sound-level estimate with history and session context.

Speaker Test

Check channels and playback with guided test signals.

Headphone Test

Check left and right channels and investigate playback issues.

Bass / Subwoofer Test

Explore low-frequency playback with tones and sweeps.

Tone Generator

Create a controlled tone at a chosen frequency.

Microphone Test

Check input, level and response before a call or recording.

Spectrum Analyzer

Inspect relative frequency content in live or local audio.

Our Principles

Useful before impressive: A clear next step matters more than an elaborate display.
Privacy by design: Microphone analysis runs locally in the browser. We explain permissions, storage and services in our Privacy Policy.
Transparent limitations: We say when a result is approximate, device-dependent or outside a tool’s purpose.
Repeatable testing: We encourage the same device, browser and setup for comparisons, and publish a validation protocol.
Free, browser-based access: You can use the core tools without an installation or signup.
Simple explanations first, technical depth second: Start with what a result means, then follow the methodology when you want the signal path and calculations.

How We Work

We start with an audio-testing problem someone can actually encounter. Then we build a controlled browser test and explain what its output can help them check. We document the limits of the device and browser path, improve instructions for repeating the test, and update tools and guidance as browser and audio behavior changes.

That work is visible in the Methodology, Validation, Editorial Policy and Changelog. Those pages let you inspect our approach instead of taking a claim of authority on faith.

What We Will Not Claim

A browser test can be useful without pretending to be a laboratory instrument.

We do not claim laboratory accuracy or Class 1 or Class 2 sound-level-meter certification.
We do not use these tools to diagnose hearing or medical conditions.
We do not claim that microphones, speakers, headphones, devices or browsers all behave the same.
We do not invent experts, reviewers, credentials, awards or certifications to support a result.

For a decision that needs calibrated acoustic measurements, regulatory evidence or medical assessment, use an appropriate instrument and qualified professional. Read our Accuracy & Limitations guide for the practical boundaries.

Where Our Information Comes From

For health and safety context, we prefer primary guidance from WHO, CDC/NIOSH, OSHA and NIDCD. For browser behavior and audio APIs, we use MDN and official technical documentation where relevant.

We keep guidance from different organizations distinct and link to the source behind a specific claim. You can inspect the technical and safety source list or read how we select and update references in the Editorial Policy.

About the Project

Decibel Meter Lab is an independently built and maintained browser-audio project.

We use “we” as the voice of the project. The tools and pages show what we make, how we explain it, and where we draw the line on claims. We do not ask you to rely on an invented founder or a claimed team size. Our Changelog records meaningful updates, and our Privacy Policy describes what happens when you use the site.

Who Uses These Tools

These tools are for anyone who wants a first check or a clearer explanation: someone comparing a room’s noise on the same device, setting up a call microphone, checking whether both headphone channels play, exploring a speaker’s bass response, or learning what a spectrum shows.

Educators, musicians, audio enthusiasts and people troubleshooting everyday setups can use them as reference tools. The right interpretation still depends on the setup and the question. Our methodology and limitations guide help you decide what a browser result can support.

Transparency & Trust

The working notes behind our claims and tools are open for you to read.

Test It Yourself

Start with a real question, try the tool, and read what the result can tell you.

Open Decibel Meter Explore all seven tools