C6 Chord on Ukulele
C6 = C – E – G – A (Root, Major 3rd, Perfect 5th, Major 6th)
C6 is the one ukulele chord that needs no fingers at all: strum the G, C, E, and A strings completely open, and the result is already a complete C6 chord. That's not a coincidence of easy voicing — it's a direct consequence of the tuning itself, since the four open pitches G, C, E, and A are precisely the four notes that make up a C major triad plus its sixth. No other common chord on the ukulele is spelled entirely by its open strings.
A sixth chord adds the sixth scale degree to a major triad, producing a warm, slightly jazzy color softer than a seventh chord's sharper tension — sixth chords were a favorite voicing in swing-era and early jazz-influenced popular song, genres the ukulele has deep historical ties to. C6 can substitute for a plain C major chord almost anywhere, adding gentle harmonic color without disrupting the song's function, and because GCEA tuning happens to spell it exactly, it's a strong candidate for ending a song on — an open, resonant final chord that needs no fretting-hand movement at all. It's worth noting this open-string identity is unique to the key of C: the same six-chord color built on other roots requires real fretting, which is part of why C6 in particular gets singled out in ukulele method books as a neat bit of tuning trivia.
Fingerings
Open Position
How to Practice It
There's no fingering to practice here, so the useful exercise is ear training: strum the open strings and consciously listen for the sixth's color against a plain C major triad, then compare it to C major fretted with the ring finger's usual third-fret A-string note — noticing how removing that fretted note and simply letting the A string ring open changes the chord from C major into C6. It's also worth using C6 deliberately as a resolution chord at the end of a simple strummed song, since it's the rare moment where the ukulele's open, unfretted ring can be the entire final chord.
Common Progressions
- I – I6 alternation, moving from plain C to the fully open C6 for color (C – C6)
- I6 – IV – V – I (C6 – F – G – C)
- vi – IV – I6 (Am – F – C6), landing the progression on the open voicing
- A closing C6 is a common way to end a simple strummed arrangement.
FAQ
- Why does C6 need no fingers on ukulele?
- Because the open G, C, E, and A strings already spell exactly the four notes of a C6 chord — root, third, fifth, and sixth — a direct result of how GCEA reentrant tuning happens to line up with that particular chord.
- Is this a coincidence unique to C6, or does it happen with other chords too?
- It's essentially unique to C6 among common chord types — no other major, minor, or seventh chord built on any root is spelled entirely by the open GCEA strings.
- What does the added sixth do to C major's sound?
- It softens and warms the chord, a gentler color than a seventh's sharper tension, closely associated with swing-era and early jazz-influenced popular song styles the ukulele has strong historical ties to.
- Can C6 be used as an ending chord?
- Yes, and it's a favorite choice for exactly that — an open, fully resonant final chord requiring no fretting-hand movement, which suits a simple strummed arrangement's closing moment well.
- Does any other common ukulele key get this same open-string trick?
- Not with a plain sixth chord in the same tidy way — the GCEA open strings are specifically G, C, E, and A, which spell C6 exactly; transposing the same chord type to another root requires real fretting, since no other root's sixth chord matches those four particular open pitches.
- Is C6 ever confused with A minor 7 on ukulele?
- The two chords share every one of their notes, since C6 and Am7 are enharmonic equivalents built from the identical four pitches viewed from different roots — which one you call it depends entirely on which note the surrounding harmony treats as the bass or functional root.
- Should a total beginner learn C6 as an early chord, given how easy it is?
- It's worth knowing early simply because it costs nothing extra to learn — since it's identical to strumming completely open strings, the real lesson isn't a new finger shape but understanding why this particular chord happens to require none at all.
C6 on other instruments: C6 on Guitar, C6 on Piano. Related: how chords are built, chord finder.