Three strings, two notes, one interval
The common cigar box guitar tuning is open G as G–D–G: root, fifth, octave. On a typical build that is G3–D4–G4 — 196.00, 293.66 and 392.00 Hz.
What makes it the default is what it leaves out. There is no third in the chord, so laying a slide straight across all three strings gives you something that is neither major nor minor — which is exactly what the blues repertoire these instruments are built for wants. It is sometimes called G modal, and sometimes the power-chord tuning, for that reason.
The first two tabs are the same three note names an octave apart — which one is right depends on your build, not on a standard. The third shows the alternatives, including the B that turns the chord explicitly major.
Which octave is your instrument in?
Here is where a cigar box guitar differs from every factory instrument on this site: there is no standard to check against. These are hand-built. Scale lengths vary with whatever neck and box the builder had, string gauges vary with what was to hand, and the same three note names work at either octave.
So the tuner is partly a way of finding out what you own. Tune to one octave and judge by feel:
- Slack, buzzing against the frets, dull tone? The strings are too light or you are an octave too low for this build. Go up.
- Uncomfortably tight, hard to fret, worrying to look at? Too high for those gauges. Go down, or fit lighter strings.
- Firm response, clear tone, comfortable under the hand? That is the octave the instrument was built for, whatever a chart says.
G3–D4–G4 tends to suit shorter scales and lighter strings; G2–D3–G3 suits longer scales and heavier ones. Neither is more correct.
Tuning routine
- Start with the 3rd string, the lowest. It is your root and everything else is measured against it.
- Then the 2nd, a fifth above. On a three-string instrument you can hear this interval clearly — play them together and the fifth should sound stable and open, with no waver.
- Then the 1st, an octave above the 3rd. Watch the octave digit here especially.
- Play all three together. This is the real check on an open-tuned instrument: three centred readings can still produce a chord that sounds unsettled, because a chord is judged by its intervals.
- Check the two Gs against each other. Play the 3rd string, then the 1st. They should sound like one note in two registers.
The other tunings worth knowing
Open D (D–A–D) is the same root–fifth–octave shape moved down, and everything transfers; it is a matter of which register suits your instrument and your voice. GBD replaces the octave G with a B, which puts the third into the chord and makes it explicitly major — brighter, more resolved, and less suited to sliding around behind a minor-key vocal.
Four-string cigar box guitars exist too, usually adding a note above or below one of these shapes. And the ancestor of the whole family, the diddley bow, has one string and no tuning question at all beyond “what pitch do you want the drone at”.
What the needle can and cannot settle
On a three-string open-tuned instrument, the tuner does a bigger share of the job than usual — there are only three pitches and no complex chord voicings to argue about. What it cannot do is play slide.
If you play with a slide, intonation is entirely yours: the slide has to sit directly over the fret rather than behind it, and any tilt puts the three strings at slightly different points, which is a chord out of tune with itself. If open strings read perfectly and slide chords sound sour, that is technique rather than tuning — the same problem the lap steel and resonator pages cover in more depth, since those are instruments built entirely around it. And in an open tuning there is always the temperament question: a major third from equal temperament sits about 14 cents above where the interval locks, which our guide to cents explains — though GDG neatly sidesteps it by having no third at all.
Frequently asked questions
What is the standard tuning for a 3-string cigar box guitar?
Open G as G–D–G — root, fifth, octave — is the most common by a wide margin, and it is sometimes called G modal or the power-chord tuning. The reason it dominates is what it does under a slide: because there is no third in the chord, a bar laid straight across all three strings gives you something that is neither major nor minor, which fits the blues repertoire these instruments are mostly built for. Open D (D–A–D) is the same shape moved down, and GBD adds a third for players who want an explicitly major chord.
Should my GDG be G3–D4–G4 or an octave lower?
Whichever your instrument was built for, and there is no universal answer because these are hand-built instruments. Scale length and string gauges vary enormously between builders, and the same three note names work at either octave. G3–D4–G4 is the common choice on a shorter scale with lighter strings; G2–D3–G3 suits a longer scale with heavier ones. Work it out from the instrument: tune to one, and if the strings feel slack and rattle against the frets, you are an octave too low for that build; if they feel dangerously tight, you are too high.
How do I know what strings to use?
Start from the tuning and the scale length, not from a packet. Sets sold specifically for three-string cigar box guitars are usually built around either GDG or GBD at a standard 25-inch scale, and those are a reasonable default. If your instrument has an unusual scale — many are built to whatever the box and neck allowed — expect to buy singles and experiment. The test is feel and sound rather than a number: a string at the right tension has a firm response and a clear tone, while one that is too light buzzes and one that is too heavy chokes.
My cigar box guitar will not stay in tune. Is that normal?
Common, and usually mechanical rather than musical. These are hand-built instruments and the tuning stability depends entirely on how well the hardware was fitted: cheap machine heads with slack in the gears, a nut slot that pinches the string so it releases in jumps, a bridge that is not seated, or a neck attached to a wooden box that flexes under tension. Work through those in order before blaming the strings. A well-built cigar box guitar holds tuning as well as a factory instrument; a poorly built one never will, however carefully you tune it.
Can I play slide on it in this tuning?
That is what it is for. An open tuning means a slide laid straight across the strings at any point gives you a chord, which is why cigar box guitars and slide playing go together so naturally. GDG in particular suits it because the absence of a third keeps the chord ambiguous, so you can play over major or minor backing without the tuning arguing with you. If you play slide, note that intonation becomes entirely your responsibility — a slide has to sit directly over the fret, not behind it, and any tilt puts the three strings in different places.