Chord Formulas
Interval structures for all common chord types. Formula uses scale degrees; intervals use half-step counts.
| Chord | Symbol | Formula | Intervals | Example (C) |
|---|---|---|---|---|
| Major | C | 1 – 3 – 5 | 4 + 3 half steps | C E G |
| Minor | Cm | 1 – b3 – 5 | 3 + 4 half steps | C E♭ G |
| Diminished | Cdim | 1 – b3 – b5 | 3 + 3 half steps | C E♭ G♭ |
| Augmented | Caug | 1 – 3 – #5 | 4 + 4 half steps | C E G♯ |
| Suspended 2nd | Csus2 | 1 – 2 – 5 | 2 + 5 half steps | C D G |
| Suspended 4th | Csus4 | 1 – 4 – 5 | 5 + 2 half steps | C F G |
| Chord | Symbol | Formula | Notes | Example (C) |
|---|---|---|---|---|
| Major 7th | Cmaj7 | 1 – 3 – 5 – 7 | Major triad + M7 | C E G B |
| Dominant 7th | C7 | 1 – 3 – 5 – b7 | Major triad + m7 | C E G B♭ |
| Minor 7th | Cm7 | 1 – b3 – 5 – b7 | Minor triad + m7 | C E♭ G B♭ |
| Minor Major 7th | CmM7 | 1 – b3 – 5 – 7 | Minor triad + M7 | C E♭ G B |
| Half Diminished | Cm7b5 | 1 – b3 – b5 – b7 | Dim triad + m7 | C E♭ G♭ B♭ |
| Diminished 7th | Cdim7 | 1 – b3 – b5 – bb7 | Dim triad + dim7 | C E♭ G♭ A |
| Augmented 7th | Caug7 | 1 – 3 – #5 – b7 | Aug triad + m7 | C E G♯ B♭ |
| Chord | Symbol | Formula | Notes | Example (C) |
|---|---|---|---|---|
| Add 9 | Cadd9 | 1 – 3 – 5 – 9 | Major triad + 9th | C E G D |
| Major 9th | Cmaj9 | 1 – 3 – 5 – 7 – 9 | Cmaj7 + 9th | C E G B D |
| Dominant 9th | C9 | 1 – 3 – 5 – b7 – 9 | C7 + 9th | C E G B♭ D |
| Minor 9th | Cm9 | 1 – b3 – 5 – b7 – 9 | Cm7 + 9th | C E♭ G B♭ D |
| Major 11th | Cmaj11 | 1 – 3 – 5 – 7 – 9 – 11 | Cmaj9 + 11th | C E G B D F |
| Dominant 11th | C11 | 1 – 3 – 5 – b7 – 9 – 11 | C9 + 11th | C E G B♭ D F |
| Major 13th | Cmaj13 | 1 – 3 – 5 – 7 – 9 – 11 – 13 | Cmaj11 + 13th | C E G B D F A |
| Dominant 13th | C13 | 1 – 3 – 5 – b7 – 9 – 11 – 13 | C11 + 13th | C E G B♭ D F A |
Chord Formulas
Reference chart for chord formulas and interval structures. Covers triads, seventh chords, extended chords, suspended, and altered chords. Free music theory reference.
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