C major 7th chord on bass (Cmaj7)

Also called or written Cmaj7 or CM7

C major 7th contains C, E, G, and B. The 8th-fret shape requires a wide stretch from the index to the pinky.

8frCGBEEADG
Positions on the neck1 of 3
Practice C major 7th chord

How it is built

CRootEMajor thirdGPerfect fifthBMajor seventh

Formula 1, 3, 5, 7

Inversions

How do you play a C major 7th chord on bass?

C major 7th is played at the 8th fret as 8 10 9 9: index finger on the E string at fret 8, pinky finger on the A string at fret 10, middle finger on the D string at fret 9 and ring finger on the G string at fret 9.

Full note and interval breakdown
StringFretFingerNote
4 (E)81C (1)
3 (A)104G (5)
2 (D)92B (7)
1 (G)93E (3)

AdvancedThe pinky must reach the 10th fret on the 3rd string while the index stays at the 8th fret, creating a wide span.

Cmaj7/G inversion

C major 7th is played at the 2nd fret as 3 3 2 4: middle finger on the E string at fret 3, ring finger on the A string at fret 3, index finger on the D string at fret 2 and pinky finger on the G string at fret 4.

Full note and interval breakdown
StringFretFingerNote
4 (E)32G (5)
3 (A)33C (1)
2 (D)21E (3)
1 (G)44B (7)

Cmaj7/B inversion

C major 7th is played at the 5th fret as 7 7 5 5: ring finger on the E string at fret 7, pinky finger on the A string at fret 7, index finger on the D string at fret 5 and middle finger on the G string at fret 5.

Full note and interval breakdown
StringFretFingerNote
4 (E)73B (7)
3 (A)74E (3)
2 (D)51G (5)
1 (G)52C (1)

Why it sounds like that

C major 7th is built from the 1, 3, 5, and 7 of the C major scale. The major 7th interval from C to B gives the chord its smooth, resolved character. Compare it to C major, which lacks the B and sounds more plain.

What goes wrong with C major 7th?

  • Letting the pinky flatten and mute the 2nd string.
  • Allowing the index finger to slide toward the 7th fret.
  • Plucking the 4th string too hard and drowning the higher notes.

When to use it

C major 7th is the I chord in C major, heard in C–F–G–C, the I–IV–V–I. It suits jazz, bossa nova, and mellow pop. Use it over C major or C 5th.

Changing to and from C major 7th

  • Sliding the shape down one fret to the 7th fret gives B major 7th.
  • From C major 7th, move the pinky from the 3rd string 10th fret to the 2nd string 9th fret to play C major.

Which voicing to use

The 8th-fret shape keeps C in the bass for a grounded sound. The Cmaj7/G inversion at the 3rd fret puts G in the bass, softening the chord. The Cmaj7/B inversion at the 7th fret has the leading tone B in the bass, creating tension that resolves to C.

Other C chords

Common questions

How is C major 7th written?

C major 7th is written CM7 or Cmaj7.

What mistake do bassists make with C major 7th?

Bassists often let the pinky collapse and buzz the 3rd string. Keep the pinky curved and press just behind the fret.

How does C major 7th sound in a higher register?

Playing C major 7th at the 12th fret gives a brighter, more bell-like tone. The same notes ring out with less low-end weight.

Why is C major 7th sometimes confused with C major?

C major 7th adds the B, the major 7th, to the C major triad. That extra note creates a dreamier, more resolved sound than C major.