Free Online Guitar Tuner

Tune your guitar online for free using your microphone. Works for acoustic, electric, bass, Standard EADGBE, Drop D, Drop C, open tunings, and custom setups.

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✓100% Free Forever
✓30+ Tunings
✓Works on Any Device

Popular Guitar Tuner Shortcuts

Start with the free guitar tuner above or jump straight to the tuning page that matches your song, guitar, or setup.

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After you tune

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Answer three questions about your level, goal, and preferred learning style. We will map out the next sessions and tell you whether free resources or a structured course are the better fit.

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App experiment

Would you buy GuitarTuner Pro?

We are testing demand for a native iPhone and Android app before building it. The web tuner stays free; Pro would be a one-time upgrade for players who want a cleaner, app-store version.

No ads

A quieter tuner screen when you are practicing or on stage.

Offline first

Open the tuner quickly even when rehearsal-room signal is rough.

Saved setups

Keep custom tunings and favorite instruments ready to go.

Proposed price

$4.99lifetime
  • Free web tuner remains available.
  • No subscription in this first concept.
  • Votes help decide whether we build native apps.

This is a demand test. There is nothing to buy yet.

How to Tune Your Guitar Online

A quiet room, one clear string, and the right target tuning are usually enough for a stable microphone tuner reading.

  1. 1

    Allow microphone access

    The tuner listens through your browser after you approve microphone permission.

  2. 2

    Choose a tuning

    Start with Standard EADGBE or pick Drop D, Drop C, open tunings, bass, or custom notes.

  3. 3

    Play one string

    Pluck a single string clearly and mute the others so the tuner can lock onto the pitch.

  4. 4

    Adjust the peg

    Tighten if the note is flat, loosen if it is sharp, and stop when the indicator centers.

  5. 5

    Recheck every string

    Run through the guitar again once string tension settles for a cleaner final tuning.

Popular Guitar Tunings & Resources

Need Something Different?

Create your own custom tuning with any number of strings and notes. Perfect for experimental tunings, extended range instruments, or unique setups.

Try Custom Tuner

Guitar Tuner FAQ

How do I use an 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. Clearly labeled partner and affiliate recommendations help keep the tuner free and ad-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.
Can I tune bass or ukulele here?
Yes. GuitarTuner.io includes dedicated tuners for bass, 5-string bass, 6-string bass, baritone ukulele, low G ukulele, and standard GCEA ukulele tuning.