Open G tuner: D G D G B D, free, with your mic

This is a free online guitar tuner, already set to Open G. The strings become D G D G B D, so the open strings sound a G major chord on their own. Only three of them move, and all three go down. Press Start, play one open string, let the note settle, then aim for 0 cents. Open D, DADGAD and standard are in the menu above the tuner, so getting there and back is one click. No account, no download. It sits alongside the rest of our free guitar tools.

What Open G tuning is

An open tuning is one where the open strings already sound a chord. Strum all six without touching the fingerboard and you get music rather than a noise. Open G is the one built on a G major chord, and the notes are D G D G B D, from the thickest string to the thinnest.

Three strings move down a whole step and three do not move at all. Nothing goes up, which is why Open G is gentle on the instrument: the total pull on the neck drops rather than rises.

Count the notes and you find three Ds, two Gs and one B. G is the root, B is the third, D is the fifth: a complete G major chord with the fifth doubled twice. The lowest string is one of those Ds, not the root, and that single fact decides a lot of what Open G sounds like. We come back to it below.

The reference pitch menu offers A at 432, 440 and 442 Hz, and opens on 440, which is what the frequencies above assume. Change it and all six targets move together.

Chords in Open G: one finger across the neck

Here is the whole appeal. Because the open strings sound a G major chord, laying one finger flat across the five thinnest strings at any fret gives you another major chord, in tune, with no shape to learn. The chord moves up by as many half steps as the fret you barre.

1. Open strings, nothing held down: G major.
2. Barre the second fret: A major.
3. Barre the fifth fret: C major.
4. Barre the seventh fret: D major.
5. Barre the twelfth fret: G major again, an octave up.

That already hands you the three chords a huge amount of roots music is built from: G at the open strings, C at the fifth fret, D at the seventh. You can play a whole song with one finger and still have a free hand, which is exactly why this tuning turns up so often in blues, country and rock rhythm playing.

Minor chords need one small change. The third of the chord is on the second string, so to turn a barre into a minor chord you put the second string one fret below the barre and leave the rest of it where it is. Barre the second fret for A major, then move the second string to the first fret, and you have A minor. The exception is the open position: there is no fret below the open strings, so G minor is the one chord you cannot reach this way.

Two colors are worth adding early, and the first one is a single fret. Count from the barre: the second string carries the third of the chord, so putting the little finger one fret above the barre on that string raises the third to the fourth and the chord becomes a suspended fourth, which wants to resolve back down. Two frets above is not a sus4 but a tritone, and it sounds like a mistake because it is one. In the open position the same move is the first fret of the second string: B goes to C, and G major becomes Gsus4. The second color needs no fretting at all: play only the three lowest strings, D, G and D, for a percussive figure that sits under a vocal without crowding it.

A capo works normally and is the quickest way to change key without retuning: at the second fret the open strings sound A major, at the fifth they sound C. The one finger barre positions shift with it, counting from the capo rather than the nut.

Slide and blues in Open G

A slide cannot bend to fit a chord shape. It is a straight bar, so it can only play what a straight line across the strings gives you. In standard tuning that line is not a chord. In Open G it is, at every fret, which is why so much bottleneck blues lives here.

• Sit the slide over the fret, not behind it. Directly above the metal, where a fretting finger would never go. Behind the fret you get a note that is flat.
• Almost no pressure. The slide rests on the strings and lets them vibrate underneath. Press and you get a rattle against the frets and a note pushed sharp.
• Mute behind the slide. Let the fingers behind it touch the strings lightly. Without that, everything between the slide and the nut rings along and the sound turns to mud.
• Arrive on the note, do not land on it. Slide into the fret from a little below and stop there. The movement is the instrument.

Tuning matters more with a slide than without it, because there is no finger pressure to pull a slightly flat string into line. Get each string to 0 cents, play the open strings together, and listen for one that beats against the others: a slow wobble in the sound rather than a clear chord.

Open G is also where a lot of hammered riff playing on the second string comes from. The B is the third of the chord, so a hammer on from the open string to the first fret and back is a move between a minor and a major third, which is the whole blues vocabulary in two notes.

Riffs and groove in Open G

Open G likes a percussive right hand. Everything already sounds big, so the work is not filling the space but deciding when the open strings are allowed to ring. Three habits do most of it.

• Palm mute the low strings. Rest the side of the hand near the bridge on the sixth, fifth and fourth strings. The D, G and D underneath turn from a ringing drone into a short, dry pulse, which is what gives a riff its edge instead of a wash.
• Accent the high strings. Let the first three ring and put the accent there, on the upbeat rather than the downbeat. The low strings keep time, the high ones carry the groove, and the two jobs stay separate.
• Hammer on the second string. That string is the third of the chord, so a hammer on from the open string to the first fret and back moves between a minor and a major third. Two notes, and it is most of the blues vocabulary. It is also the single most recognizable move in the tuning.

Build it in that order rather than all at once. One barre, slowly, with the palm mute. Then two positions. Then a short riff. Work it with a metronome at a tempo where the low end stays readable, and only then take the tempo up: Open G amplifies what your right hand is already doing, and it amplifies a vague groove just as faithfully as a tight one.

The sixth string: keep it or drop it

In Open G the lowest string is a D, which is the fifth of the chord rather than its root. Strum all six and the chord has its fifth in the bass. It is still a G major chord, but it sits open and slightly unresolved rather than planted. That is not a flaw, and it is also not what everyone wants.

• Keep it, and you get the drone. The low D rings under everything, and because the fourth and first strings are also Ds, you have the same note at three octaves. Chords up the neck float over a bass that never moves. This is the ringing, wide sound the tuning is known for.
• Leave it out, and you get the root. Play from the fifth string up and the chord starts on G, in root position, firm and unambiguous. Most rhythm playing in Open G does this, which is why the one finger barre above is written across five strings and not six.

There are three ways to leave it out, and they are all normal. Start the strum from the fifth string. Rest the thumb or the side of the hand on the sixth string to mute it. Or take it off the guitar entirely.

That last one is where the habit comes from, and it has a name attached to it. Keith Richards plays a good deal of the Rolling Stones rhythm repertoire in Open G on a five string guitar, with the sixth string simply removed: the chord starts on its root, the hand never has to think about the string it is avoiding, and the part sits in a narrower, harder band of the sound than six strings would. That is a specific instrument set up for a specific job, not a general recommendation.

Open G vs Open D vs DADGAD

These three are the tunings most players meet first, and they are not interchangeable. Open G and Open D are both open major chords, and the chord is a fourth apart, although both tunings sit on the same low D string. DADGAD is the odd one out: it has no third in it, so it is neither major nor minor. All three are presets in the menu above the tuner, and you can also open this page straight onto one by adding a tuning parameter to the address.

How to choose, in one line each. Take Open G for blues slide, for roots rhythm playing and for the looser, rootless feel it has when the sixth string is left out of the way. Take Open D when you want the root at the bottom of the chord and a big ringing accompaniment in D. Take DADGAD when you want a melody to sit on top of a drone without the chord underneath committing to a mood.

A lot of blues, country and roots rock lives in Open G, and plenty of rock rhythm playing too. We are not going to put a list of titles on a tuning page: the tuning belongs to no one, and a list of names will not help you get your guitar in tune.

If you would rather keep every chord shape you already know and only gain a low D, the Drop D tuner is the gentler door: one string moves and nothing has to be relearned. For standard tuning and the full list of presets, go to the online guitar tuner, and for the method itself, with a tuner or by ear, how to tune a guitar is the door.

Who made this

Guitar Social Club is the work of Yohann Abbou, a guitar teacher in Paris. He teaches adults, which shapes everything here: people with jobs, limited practice time and a clear idea of the songs they want to play. The tools come out of his lessons, which is why none of them asks you to sign up before it works, and why this one shows you cents rather than a green light. The rest of our free guitar tools work the same way.

More about Yohann and how these tools are made.