Online Tuner
Play a note and see how many cents sharp or flat it is. The microphone is only used while the tuner is on.
The microphone is only on while the tuner is running. Nothing is recorded or sent.
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Stopped
The pitch of A above middle C, 415 to 466 Hz. Most music uses 440.
A string counts as in tune within ±5 cents. Tune one string at a time, in a quiet room, and let the note ring.
How it works
- Allow microphone access when the browser asks.
- Play one note at a time.
- Adjust the string until the needle sits in the middle.
How the tuner finds the note
The tuner reads the microphone in short frames and finds the repeat period of the sound with the YIN algorithm, which gives the fundamental frequency even when the overtones are louder than the note itself. Frames that are quiet or not clearly pitched are ignored, and a short median smooths the needle without making it slow.
The needle shows the distance from the target in cents, a hundredth of a semitone. A note within 5 cents counts as in tune. Everything runs on your device: the microphone is on only while the tuner is running and nothing is recorded or sent anywhere.
Instruments and the A4 reference
Chromatic mode names the nearest note. The guitar (standard EADGBE), bass (EADG), ukulele (GCEA) and violin (GDAE) presets pick the nearest open string and show how far you are from it, which avoids confusion when a string is far out of tune.
A4 is the pitch of the A above middle C and defaults to 440 Hz. You can set it from 415 to 466 Hz, for example 415 Hz for Baroque music or 432 Hz if you prefer it.
Getting a good reading
- Play one note at a time and let it ring; a pluck or bow noise settles after a moment.
- Use a quiet room and hold the microphone near the instrument.
- Low bass notes are weak on laptop and phone microphones; play a little harder or use the 12th-fret harmonic.
- Mute the other strings so they do not ring along.
Questions
Why does the browser ask for the microphone?
A tuner has to hear the instrument. Audio is analysed live on your device and is not stored or uploaded. Stop the tuner and the microphone is released.
The tuner says nothing is heard. What is wrong?
Check the input level bar moves when you play. If not, pick the right microphone in your system or browser settings, move closer, and make sure another app is not using it.
Why does the needle jump to a different octave?
Very rich or very quiet notes can confuse any pitch detector. Choose the matching instrument preset, which limits the range it listens to, and let the note ring.
Can I tune a voice or a wind instrument?
Yes, in chromatic mode. Sustained notes work best; voices with heavy vibrato will show a moving needle.
Does it work with a tuning clip or an electric guitar cable?
It works with any input the browser lists as a microphone, including an audio interface. Choose it as the system input first.