How do I use the online guitar tuner?

Allow microphone access, choose your tuning, then play one string at a time. The tuner shows whether the note is sharp, flat, or in tune so you can adjust the tuning peg until the note is centered.

Is this guitar tuner free?

Yes. GuitarTuner.io is free to use in your browser with no account, paid upgrade, or app download required. Display ads and affiliate links help keep the tuner free.

Does the tuner use my microphone?

Yes, the tuner uses your browser microphone permission to detect pitch in real time. Audio is processed in the browser for tuning feedback.

What guitar tunings are supported?

The tuner supports Standard, Drop D, Drop C, Half Step Down, open tunings like Open G and Open D, DADGAD, bass tunings, and custom tunings with any string notes you choose.

Can I tune guitar on my phone?

Yes. The tuner works on iPhone, Android, tablets, and desktop browsers. Open the site, allow microphone access, and tune without installing an app.

Guitar Tuner

The best free online guitar tuner. Tune your acoustic, electric, or bass guitar instantly using your microphone. Accurate chromatic tuning for Standard, Drop D, Open G, and 30+ alternate tunings.

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✓30+ Tunings

✓Works on Any Device

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Guitar Tuner FAQ

How do I use the online guitar tuner?: Allow microphone access, choose your tuning, then play one string at a time. The tuner shows whether the note is sharp, flat, or in tune so you can adjust the tuning peg until the note is centered.
Is this guitar tuner free?: Yes. GuitarTuner.io is free to use in your browser with no account, paid upgrade, or app download required. Display ads and affiliate links help keep the tuner free.
Does the tuner use my microphone?: Yes, the tuner uses your browser microphone permission to detect pitch in real time. Audio is processed in the browser for tuning feedback.
What guitar tunings are supported?: The tuner supports Standard, Drop D, Drop C, Half Step Down, open tunings like Open G and Open D, DADGAD, bass tunings, and custom tunings with any string notes you choose.
Can I tune guitar on my phone?: Yes. The tuner works on iPhone, Android, tablets, and desktop browsers. Open the site, allow microphone access, and tune without installing an app.