1. Start with the root
The letter at the beginning is the chord’s root: C, F♯, B♭ and so on. Accidentals belong to the root unless they appear later in parentheses or beside an extension.
F♯m7Root: F♯ · Quality: minor · Seventh: minor seventh
2. Read the quality
No quality marker normally means a major triad. m means minor, dim means diminished and aug or + means augmented. The quality determines the third and sometimes the fifth.
- C = C–E–G
- Cm = C–E♭–G
- Cdim = C–E♭–G♭
- Caug = C–E–G♯
3. Add sevenths and extensions
A plain 7 means a minor seventh above a major triad: C7 is C–E–G–B♭. maj7 uses B natural. Numbers such as 9, 11 and 13 imply a seventh and add colour tones above it.
4. Apply alterations last
Symbols such as ♭9, ♯11 and ♭13 change only that degree. sus2 or sus4 replaces the third. A slash chord names the bass after the slash: C/E is a C major chord with E in the bass.