Open C Tuning (C G C G C E)

Open C tunes the strings from low to high to C G C G C E, so the open strings sound a C major chord. From standard, string 6 goes down two whole steps, strings 5 and 4 down a whole step, string 2 up a half step, and strings 3 and 1 stay.

Strings 6 → 1: C2 G2 C3 G3 C4 E4
From standard: Strings 6 5 4 2 change
Open strings: C (C E G)

Tuner · Open C

A4 · 440 Hz

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Mic off

±0 ¢

Auto string detect

Uses your microphone. Audio stays on this device. No mic? Tap a string to hear its note.

TuningC G C G C E

Strings · tap to hear

How to tune to open C from standard

String 6: E2 → C2, down 4 semitones · tension −37 %
String 5: A2 → G2, down 2 semitones (whole step) · tension −21 %
String 4: D3 → C3, down 2 semitones (whole step) · tension −21 %
String 3: G3 → G3, no change
String 2: B3 → C4, up 1 semitone (half step) · tension +12 %
String 1: E4 → E4, no change

The tuner above is locked to C G C G C E, so each string reads against its own target. Tap a string button to hear its note.

Open C (C G C G C E) chords

Frets are listed from string 6 to string 1 (× = do not play). The notes line is what each string sounds in this tuning.

C · all open

Frets 0 0 0 0 0 0

C G C G C E

I (home chord). Strum all six strings and let the low C ring.

F · barre fret 5

Frets 5 5 5 5 5 5

F C F C F A

IV. Flat finger across fret 5.

G · barre fret 7

Frets 7 7 7 7 7 7

G D G D G B

V. Two frets above F. C, F and G cover most folk songs in C.

Am · two fingers

Frets × 2 0 2 0 0

× A C A C E

vi. Fret 2 on strings 5 and 3, skip string 6. The open C and E strings complete the chord.

Dm · four strings

Frets × × 2 2 2 1

× × D A D F

ii. Index on string 1, fret 1; three fingers on fret 2. Strum strings 4 to 1.

Any straight barre is a major chord, named by counting half steps up from C: fret 2 = D, fret 4 = E, fret 5 = F, fret 7 = G, fret 9 = A, fret 12 = C an octave up.

Why open C sounds so big

The bass is C2, four half steps below the standard low E, the lowest note of any open tuning on this site. Three strings are C and two are G, so the open chord is mostly root and fifth spread over more than two octaves, with a single E on top as the major third.

The lower three strings form a stack of fifths and fourths (C G C), which gives open C its organ-like drone. With the third only on string 1, the low strings stay neutral and a melody on the top string colours the chord.

Open C is unusual in moving strings both ways: string 2 goes up from B to C while the bass strings go down. That mix is why it takes a moment longer to settle than the other open tunings.

Note	Open strings
C	3 of 6
E	1 of 6
G	2 of 6

What open C is used for

Solo acoustic fingerstyle and songwriting: the low C drone under a melody on strings 1 and 2 fills the room without a second instrument.

Slide on a resonator or acoustic guitar in C, a key that fits many voices: open strings for C, fret 5 for F, fret 7 for G.

Playing in open C: practical notes

Tension: string 6 drops four half steps and loses over a third of its tension, so with light strings it can flap and buzz. A heavier low string (or a medium set) keeps it clear. String 2 goes up a half step, a small increase.

Tune string 6 last and check it twice: as the bass strings loosen, the neck relaxes slightly and the strings you tuned first drift.

Back to standard: raise string 6 two whole steps (C to E), strings 5 and 4 a whole step, lower string 2 a half step, then recheck all six.

FAQ

Which strings change from standard?

Four. String 6 from E to C (down two whole steps), string 5 from A to G and string 4 from D to C (down a whole step each), string 2 from B to C (up a half step). Strings 3 and 1 stay G and E.

Will the low C string be too loose?

With light strings it can be. Same string, four half steps lower, means about 37% less tension, so it can buzz under a hard strum. A heavier gauge for string 6 fixes it.

Is open C good for beginners?

For strumming, yes: the open strings are a full chord and one finger flat across fret 5 or 7 gives F and G. The low string takes careful tuning, so use the tuner above.

Is there an open C tuning chord chart?

Yes, the chord shapes above are the chart: C with all strings open, F with a barre at fret 5, G with a barre at fret 7, plus Am and Dm. Any straight barre is a major chord: fret 2 is D, fret 4 is E, fret 5 is F, fret 7 is G, fret 9 is A and fret 12 is C an octave up.

The key of C majorthe open strings ring a C chord
Standard tuning (EADGBE)back to the reference tuning
Guitar tunerswitch tunings, or tune back to standard
Capo calculator and chord transposercapo shapes for any key
Open G (DGDGBD)same family of tuning
Open D (DADF♯AD)same family of tuning
All guitar tuningsopen, drop and modal, compared