Start the test, speak, and watch the meter respond. Record a five-second clip and play it back to hear exactly what your mic picks up. Audio stays on this device — nothing is uploaded.
How this test works
When you press start, the browser asks for microphone access and hands this page a live audio stream. The stream feeds a Web Audio AnalyserNode, which exposes the raw waveform samples. From each frame of samples the page computes the RMS level — the running average of signal energy — and converts it to dBFS for the meter and readout. The waveform display draws the same samples directly, so what you see is exactly what the browser is receiving after its input processing.
The record-and-playback check uses the MediaRecorder API to capture roughly five seconds into an in-memory buffer and immediately play it back through your speakers. Because it captures the processed stream, it answers the practical question — what do other people actually hear on a call from this microphone? The clip is never written to disk or sent anywhere, and it is discarded the moment the page closes.
One caveat worth knowing: browsers apply echo cancellation, noise suppression, and automatic gain control to microphone input by default. This is the right default for calls, but it means the meter reflects the processed signal, not the raw capacitor voltage. If your level seems to drift up or down on its own, that is automatic gain control doing its job.
Frequently asked questions
Is my audio uploaded or stored anywhere?
No. The level meter, waveform, and recording all run inside your browser using the Web Audio API. Nothing is transmitted to a server, and the test recording is held only in memory — it is gone when you leave the page.
The meter isn't moving. What should I check?
First confirm the browser has microphone permission (the icon in the address bar) and that the right device is selected in the dropdown. Then check the operating system: on Windows, Settings → Privacy → Microphone; on macOS, System Settings → Privacy & Security → Microphone. A physical mute switch or muted headset button is the most common culprit.
Why does my recording sound different from my real voice?
Browsers apply processing by default — echo cancellation, noise suppression, and automatic gain control — because most microphone use is calls. That processing can make a recording sound flatter or quieter than expected. Hearing your own voice also always sounds unfamiliar, since you normally hear it partly through bone conduction.
How do I fix "permission denied"?
Click the camera/microphone icon in the address bar and set microphone access to Allow, then reload. If you previously chose Block, the browser remembers it — you must change it in site settings; the page cannot re-ask on its own.
What do the level numbers mean?
Levels are shown in dBFS — decibels relative to the loudest signal the system can represent, where 0 is the ceiling. Normal speech typically reads between −30 and −12 dBFS. Constantly hitting 0 means clipping and distortion; never rising above −50 usually means the input gain is set too low.