This online guitar tuner listens through your phone or computer microphone, figures out which string you played and shows whether it's flat or sharp, with a needle and cents. Acoustic, classical (nylon-string) and electric guitars all use the same notes, so it works as an electric guitar tuner too.
Besides standard tuning it has drop D, half step down (E♭ standard), whole step down (D standard), drop C, open G, open D, DADGAD, 7-string guitar (low B, the low C of Brazilian choro, or Russian open G) and 12-string guitar. It all runs in your browser: the sound never leaves your device.
How to use it
- Tap Turn on microphone and allow access.
- Choose the Tuning. If in doubt, leave it on Standard.
- Play an open string and let it ring. Its button lights up and the needle shows how far off it is: up arrow (↑), tighten the tuning peg; down arrow (↓), loosen it.
- When a string stays in the green (±5 cents) for a second, it gets a ✓. Keep going until every string is done.
- Want to hear the note first? Tap the string's button: the tuner plays the reference pitch and locks onto that string. Auto goes back to detecting strings on its own.
Guitar string notes
From the 6th string (the thickest, low E) to the 1st (the thinnest, high E): E A D G B E, which beginners remember as "Eddie Ate Dynamite, Good Bye Eddie". With A = 440 Hz the frequencies are 82.4, 110, 146.8, 196, 246.9 and 329.6 Hz. A 12-string uses the same notes, but the four lower pairs add a thinner string an octave higher; the tuner shows both notes of each pair.
Popular alternate tunings
Half step down (E♭ standard, or "semitone down" in the UK) is common in rock and worship bands because it eases the vocals; the tuner spells it with sharps (D♯ G♯ C♯ F♯ A♯ D♯), the same pitches as E♭ A♭ D♭ G♭ B♭ E♭. Drop D lowers only the 6th string to D. DADGAD is a Celtic favorite and open G a slide and blues staple. On 7-string guitars, metal and jazz players add a low B, while Brazilian choro players tune the 7th string to C.
Tips
- Tune up to the note: if you go past it, loosen a little and come back up. The string holds better.
- Play one string at a time and mute the others with your hand; several strings ringing together confuse the reading.
- New nylon strings keep stretching for days: tune, play for a while and tune again.
- For an electric guitar without an amp, hold the phone close to the strings, near the pickups.
- Finish by checking the 6th and 5th strings again: tuning the others changes the tension on the neck.
Frequently asked questions
How do I tune my guitar with an online tuner?
Open this page, turn on the microphone and play one string at a time, letting it ring. Follow the arrow until it turns green. No app to install and no sign-up.
What are the notes of standard guitar tuning?
From the 6th string to the 1st: E, A, D, G, B and E (EADGBE). The 6th string is low E (E2) and the 1st is high E (E4), two octaves higher.
How do I tune my guitar to drop D?
Choose Drop D and lower the 6th string a whole step, from E to D. The others stay the same: D A D G B E. It's popular in rock and in solo acoustic arrangements.
How do I tune a guitar half a step down (E flat)?
Choose Half step down and tune as usual. Every string drops a half step: E♭ A♭ D♭ G♭ B♭ E♭, which the tuner shows as D♯ G♯ C♯ F♯ A♯ D♯.
Which string should I tune first?
Most players start with the low E and work up to the high E, then check them all once more, because tightening one string slightly changes the others. With this tuner the order doesn't matter: it detects whichever string you play.
Why does my guitar go out of tune so quickly?
New strings that are still stretching, changes in temperature or humidity, or a loose tuning machine. Tune up to the note and check again after a few minutes of playing.
Can I tune a 12-string or 7-string guitar with this tuner?
Yes. Choose 12-string to see both notes of each pair, or one of the 7-string options: low B (metal, jazz), low C (Brazilian choro) or Russian open G (D G B D G B D).
Is an online guitar tuner as accurate as a clip-on tuner?
In a quiet room, yes: detection is accurate to about a cent, well inside the ±5 cents counted as in tune. A clip-on reads vibration through the headstock, so it wins on a noisy stage. For notes other than the open strings, use the chromatic tuner.