Online Instrument Tuner

Tune by ear with your microphone: see the note, exact frequency and how many cents sharp or flat you are. Presets for guitar, bass, ukulele and violin, plus chromatic mode.

Enable your mic and play a note.

How to tune

Tap Enable microphone and allow access, pick your instrument, then play one string or note at a time and let it ring. The needle swings toward the centre as you get closer; when the note turns green and reads in tune, you're within a few cents. Positive cents mean the note is sharp (tune down); negative means flat (tune up).

Private and live. Your microphone audio is analysed in real time in the browser and is never recorded or uploaded. Tune in a quiet room, mute the strings you're not tuning, and pluck firmly for low bass notes.

Standard tunings

Guitar E A D G B E · Bass E A D G · Ukulele G C E A · Violin G D A E. Choose a preset and the target strings appear; the one nearest your played note lights up so you can see which string you're on.

Frequently asked questions

How does an online tuner work?

It analyses your mic audio with autocorrelation pitch detection to find the fundamental frequency, matches it to the nearest note, and shows the difference in cents.

Is it accurate enough for guitar?

Yes — within a few cents in a quiet room. Play one string at a time and let it ring.

Does it record my audio?

No — it's analysed live in your browser, never recorded or uploaded.

What are cents?

A hundredth of a semitone. 0 is perfectly in tune; positive is sharp, negative is flat.

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