Free Online Tool

Online Tuner

Tune any instrument in your browser using your device microphone. Free, instant, no signup.

How to tune your instrument

Hit Start Tuning and allow microphone access when your browser asks. Then play any string on your instrument and hold the note steady.

The needle tells you everything: if it swings left your string is flat (too low) — tighten the tuning peg. If it swings right, the string is sharp (too high) — loosen it slightly. When the needle centers and turns green, you're in tune.

Make small adjustments and let the note ring out fully after each turn of the peg. Strings can take a moment to settle, especially if they're new.

What is a tuner?

Every musical note has a specific frequency — a precise number of vibrations per second measured in Hz. When a string is in tune, it vibrates at exactly the right frequency for its note. A tuner listens to your instrument, measures that frequency, and tells you how close you are to the target.

String instruments go out of tune constantly: temperature changes, humidity, stretching strings, and just playing all affect the tension. Tuning before every session is a basic habit every musician needs.

This tuner is chromatic, meaning it recognizes all 12 notes — not just the open strings of one specific instrument. It works for any instrument in any tuning. Everything runs in your browser; no audio leaves your device.

Standard tunings

Each dot marks a note in that instrument's standard tuning. Brighter columns are shared by more instruments.

G 9/9 D 8/9 A 8/9 E 6/9 C 3/9 B 2/9
Guitar
Bass guitar
Ukulele
Banjo
Mandolin
Violin
Viola
Cello
Double bass

G, D and A are the most universal — they appear in guitar, bass, mandolin, and the entire violin family (violin, viola, cello). Standard tuning only; drop, open, and alternate tunings vary.

Frequently asked questions

What does "chromatic" mean in a tuner?

A chromatic tuner listens for any of the 12 notes in Western music — C, C#, D, D#, E, F, F#, G, G#, A, A#, B — and their octaves. This is different from tuner apps that only know about the standard open strings of one specific instrument. Because it covers every note, it works for any instrument in any tuning.

How accurate is this tuner?

The tuner uses an autocorrelation algorithm that resolves pitch to within about 1–2 cents (there are 100 cents per semitone, so that is well below what the human ear can hear as out of tune). The main variable is your microphone — a built-in laptop mic is usually sufficient, but a noisy room or a very quiet room can occasionally cause the needle to waver.

The tuner is showing the right note but the wrong octave — is something broken?

No, the string is still in tune. Very low strings (like the open E on a bass or guitar) sit near the edge of the detection range, and sometimes the algorithm latches onto a harmonic overtone rather than the fundamental frequency. The note name is what matters for tuning — if it says E and you're playing E, you're good.

Does it work on a phone or tablet?

Yes. The tuner runs on the Web Audio API, which works in Chrome on Android and Safari on iPhone and iPad. When you tap Start Tuning, your browser will ask for microphone permission — allow it and you're ready to go.

Is my audio sent anywhere?

No. Everything runs locally in your browser. The microphone signal goes directly into the Web Audio API, the pitch is calculated on your own device, and nothing is uploaded or stored anywhere.