American chord symbols: major, minor, 7th and their variants

The common language of modern music

Walk into any jazz, pop, or rock rehearsal anywhere in the world. On the music stand you'll probably see a sheet with capital letters: A, Dm, G7, Cmaj7, F#m7b5. Without a single note written on a staff, that sheet tells the guitarist exactly which chords to play and in what order.

That system is the American chord symbol notation — also called lead sheet notation or simply chord symbols — and it is today the most widespread way of communicating harmony in popular music, jazz, folk, and any context where musicians improvise, accompany, or read repertoire quickly.

For a guitarist, understanding this system is not optional. It is the alphabet of the music you will play most.

The foundation: seven letters

American chord notation uses seven letters of the alphabet to name the notes: A, B, C, D, E, F, G, which correspond to La, Si, Do, Re, Mi, Fa, Sol. Here lies the fundamental difference from the Latin system: in American notation, A is La, B is Si, C is Do. Once this mapping is internalized, the rest of the system is completely logical.

Accidentals are added directly to the letter: F# is F sharp, Bb is B flat, Eb is E flat. The sharp is written with the # symbol and the flat with a lowercase b in contexts where the ♭ symbol is unavailable.

Major and minor chords

The most basic building block of chord notation is the distinction between major and minor. A major chord is written with the letter alone in uppercase: C is C major, G is G major, A is A major. Without any addition, a lone letter always indicates a major chord.

A minor chord is written with the letter followed by a lowercase m or min: Am is A minor, Dm is D minor, Em is E minor. On the guitar, Am, Dm, and Em are three of the most used open chords — especially in folk, flamenco, and Spanish-language pop. Recognizing them in a chord chart and translating them to the fretboard is the first practical step.

Seventh chords

The next layer of complexity is seventh chords. The dominant seventh (7) is written with the letter followed by 7: G7 is G dominant seventh, the tension chord par excellence. In a 12-bar blues, almost all the chords are dominant sevenths. The major seventh (maj7) adds a softer, more floating sound, very common in jazz and bossa nova: Cmaj7 is C with a major seventh.

The minor seventh (m7) such as Am7 is one of the most used chords in modern pop and jazz. The progression Am7 – D7 – Gmaj7 is a ii-V-I in G major, the basic cell of tonal jazz. There is also the diminished seventh (dim7 or °7), with a very tense and chromatic sound, and the half-diminished (m7b5 or ø), frequent as ii° in minor keys.

Extensions and modifiers

The system can continue stacking thirds: the 9th (9 or add9), the 11th (11 or sus4), and the 13th (13). The suspended fourth (sus4) is especially common in guitar: Asus4 is A with the fourth suspended in place of the third, an open chord that doesn't clearly define major or minor. The distinction between add9 (no seventh) and 9 (with dominant seventh) matters.

The modifiers b and # alter specific notes: G7b9 is G seventh with a flat ninth; C7#11 is the characteristic Lydian dominant chord of modern jazz. The sus modifier replaces the third with the second (sus2) or the fourth (sus4). The add modifier adds a note without including the seventh: Gadd9 is G major with the ninth but no seventh.

Slash chords and reading in practice

A very common convention is the slash chord, written with a forward slash: C/E means C major with E in the bass, G/B is G major with B in the bass. This notation is especially useful for the accompanying guitarist, indicating not just which chord to play but which note should sound on the lowest string.

When you see Am – F – C – G you immediately recognize one of the most used progressions in pop in a minor key. When you see Dm7 – G7 – Cmaj7 – Fmaj7 you recognize a ii-V-I-IV in C major: it's jazz. Chord symbols are a harmony score, not a performance score: they define the harmonic content and leave the performer free to decide the texture, rhythm, and articulation.

In the next post we will learn to read a lead sheet: the combination of melody on the staff and chord symbols that is the standard format in jazz and pop for communicating a complete song on a single page.

Chords are words. Chord symbols are the vocabulary. But music is the conversation. — Bill Evans