How to Read Chord Symbols: Every Letter, Number and Circle

Read a chord symbol from left to right. The capital letter is the root note, the marks right after it give the chord’s quality (nothing for major, m for minor, dim or a small circle for diminished, aug or + for augmented), numbers add notes on top, and anything after a slash is the bass note. So Am7/G means an A minor chord with its 7th added (A C E G), played with G as the lowest note.

What do m and M mean in chords?

Every chord symbol starts with a capital letter from A to G. That letter is the root: the note the chord is built on and named after. A sharp or flat sign right after the letter belongs to the root, so F# is F sharp major and Bbm7 is B flat minor seventh.

A letter on its own means a major triad: three notes, the root plus the third and fifth above it. C is C E G. A lowercase m after the letter makes it minor by lowering the middle note, the third, by one half step (the very next key on a piano, black or white): Cm is C Eb G. That single half step is what turns a bright chord into a sad one.

Minor has a few spellings. Pop and guitar charts use m, other charts write min or mi, and jazz lead sheets often use a minus sign. Cm, Cmin, Cmi and C- are all the same chord.

Capital M means major, and it is easy to misread, because it looks so much like m. You mostly see it in CM7, which is Cmaj7. Side by side:

If a handwritten chart leaves you guessing between M and m, check the key. In C major the chords built on D, E and A are minor, and the only major sevenths are Cmaj7 and Fmaj7. So a smudged DM7 or Dm7 in a C major song is far more likely to be Dm7 (D F A C).

What do the numbers in chords mean? 7, maj7, 9 and add9

A number names a note to add, counted up the major scale of the root with the root as 1. On C, the 2 is D, the 4 is F, the 6 is A and the 7 is B. Past the octave the count keeps going, so 9 is D again, 11 is F and 13 is A.

The exception is 7. A plain 7 means the flat seventh, a whole step below the octave: C7 is C E G Bb, the dominant seventh chord. To get B, the seventh straight from the scale, the symbol has to say maj7. An m before the 7 only describes the triad underneath, so Cm7 is C Eb G Bb. The seventh chord entry covers the whole family, including the rarer minor-major seventh, Cm(maj7).

Bigger odd numbers bring the lower ones with them. C9 is C E G Bb D, so the 9 includes the flat 7. C13 includes the 7 and the 9 as well, though players usually leave out the 11 (F), because it grinds against the E. If you want the 9th with no 7th, the symbol says add: Cadd9 is C E G D. That one missing note is the big split in the ninth chord family. C9 sounds bluesy and funky, and Cadd9 sounds like a bright major chord with a sparkle on top.

C5 is the odd one out: a power chord, only the root and fifth, with no third to make it major or minor. It is the standard chord for distorted rock guitar because it stays clear under heavy gain.

A 6 always means the major sixth, even on a minor chord: Cm6 is C Eb G A. A flat or sharp before a number bends that note: C7b9 is C E G Bb Db, and C7#9 is C E G Bb D#, the 7#9 chord Jimi Hendrix used in “Purple Haze” (in E, as E7#9). Parentheses only keep the extras tidy, so C7(b9) and C7b9 are the same chord.

You rarely need every note of a big chord. Keep the 3rd and the 7th, since those two decide the flavor, and drop the 5th first. For C13, the four notes C, E, Bb and A cover it: the root, the 3rd and 7th, and the 13th that gives the chord its name.

Sus, dim and aug: the three-letter symbols

Sus means suspended: the third comes out and another note takes its place. Csus2 uses the 2nd (C D G) and sounds open and hollow. Csus4 uses the 4th (C F G), and its F wants to fall to E, which turns it back into plain C. Sus with no number means sus4, so Gsus is G C D. Add a 7 and it stacks on top: G7sus4 is G C D F. Add is a different instruction: Cadd2 (C D E G) keeps the E, and Csus2 (C D G) drops it.

Dim means diminished: a minor chord with its fifth lowered by a half step. Cdim is C Eb Gb, two minor thirds stacked up. Every major key has one on its 7th step; in C major it is Bdim, B D F. It sounds tense, and its B wants to rise a half step to C, so Bdim usually leads into a C chord. Cdim7 adds one more minor third on top: C Eb Gb Bbb, where Bbb is the same piano key as A. Its notes sit three semitones apart all the way round, so there are only three different dim7 chords. The diminished chord entry has more on both.

Aug means augmented: a major chord with its fifth raised a half step. Caug is C E G#. It is symmetrical too, with four semitones between each note, so Caug, Eaug and G#aug use the same three piano keys. It sounds unresolved and dreamlike, and works best as a passing chord: in the run C, Caug, F, the G rises to G# and then to A.

What do the circle and triangle mean in chords?

The little circle is shorthand for diminished, common on jazz lead sheets. B° means Bdim (B D F), and B°7 means Bdim7 (B D F Ab). Some jazz charts write a plain B° and mean the four-note chord, so if the melody sits on an Ab over a B°, play Bdim7.

A circle with a line through it, ø, means half-diminished: a diminished triad with a flat seventh on top, the same chord pop charts write as m7b5. Bø7 is Bm7b5, B D F A. It is the chord on the 7th step of any major key once you add sevenths. The full circle and the crossed circle differ by one top note: B°7 has Ab and Bø7 has A.

The triangle, Δ, is jazz shorthand for major seventh. CΔ7 is always Cmaj7 (C E G B). A bare CΔ is the ambiguous one: some writers mean Cmaj7 and others mean a plain C triad. Try Cmaj7 first, and if its B rubs against a C in the melody, drop the B.

Roman numerals borrow the same marks: vii° is the diminished chord on the 7th step, viiø7 is its half-diminished seventh, and a + marks an augmented chord. Open the free online chord player in C major and switch to 7ths: each pad shows a numeral and a chord name, and the seventh pad reads viiø7 and Bm7b5. Gelato Chord labels each of its seven keys with the chord name as well, so flipping it between triads and 7ths lets you read the new symbol and hear the added note at the same moment.

What does the slash mean in chords?

A slash splits a chord symbol in two: the chord on the left, and on the right the note that goes lowest, in the bass. C/G, said “C over G”, is a C major chord with G as the bottom note, and the whole thing is called a slash chord.

When the bass note belongs to the chord, the slash is asking for an inversion. C/E puts the third on the bottom (first inversion) and C/G puts the fifth there (second inversion). The notes are the same as a plain C; only the order changes, and C/G in particular sounds like it is waiting for the next chord.

When the bass note is not in the chord, the slash adds a note. D/C is D F# A over a C, which sounds like a D7 with its 7th in the bass. F/G, an F triad over a G, is a smooth soul and gospel sound that stands in for a plain G chord right before C.

Most slash chords exist to make a bass line walk. Play C, C/B, Am, Am/G, F and listen to the bottom: C, B, A, G, F, a scale stepping down while the chords above barely move.

To play one:

• Piano: the left hand plays the note after the slash, the right hand plays the chord.
• Guitar: find a shape with that note lowest. Reading frets from the low E string (x means skip it), C/G is 332010, D/F# is 200232 and G/B is x20003.
• Bass: play only the note after the slash. The chord on the left is for everyone else.

Not every slash is a bass note. In C6/9 the slash joins two added notes, the 6th and the 9th, so the chord is C E G A D with C still on the bottom. A full chord name written above another chord, with a horizontal line between them like a fraction, is a polychord: play both chords at once, the top one over the bottom one. And N.C. means no chord: the chord players stop until the next symbol, while the melody carries on.