Reading the meter
The scale is in cents — hundredths of a semitone. The green band is ±5 cents, which is closer than a guitar can hold anyway once you bend a note or the room warms up. Anywhere in that band is in tune.
The tuner names the string it thinks you are playing, so you do not have to select one. In chromatic mode it names the nearest note instead, which is what you want for slide, alternate tunings or any other instrument.
Getting a stable reading
Play one string, cleanly, and let it ring. Two strings at once give the detector two competing fundamentals and the reading jumps. Pluck near the bridge for a clearer fundamental, and mute the strings you are not tuning.
Always tune up to the note. If you are sharp, drop below the target and come back up — that takes the slack out of the tuning peg and the string holds much better.
Why the browser's audio processing is switched off
Browsers normally apply echo cancellation, noise suppression and automatic gain to microphone input, all tuned for speech on video calls. Every one of them mangles a sustained musical note — noise suppression in particular treats a steady tone as background hum and removes it.
This tuner requests the raw stream with all three disabled, which is why it stays stable on a quiet, sustained string where a naive implementation flickers.
Frequently asked questions
Why does it need microphone access?
The audio is analysed live in the page and never recorded or sent anywhere. Browsers also only allow microphone access over HTTPS, so the page must be loaded securely.
Is it accurate enough for recording?
The detector resolves well under a cent on a clean signal, which is finer than a guitar stays in tune between songs. For studio work the limit is the instrument's intonation, not the tuner.
Is my audio uploaded?
No. The pitch detection runs in the page — the file never leaves your device.
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