Chord Notation Reference

Harmonybeam accepts standard chord notation with wide tolerance for how you write it. If you’ve seen a chord written a certain way in a real book or lead sheet, it probably works.

Root notes

Any note name A–G, with optional sharp or flat:

C  C#  Db  D  D#  Eb  E  F  F#  Gb  G  G#  Ab  A  A#  Bb  B

Unicode ♯ and ♭ also work (e.g. F♯m7).

Basic chord types

Symbol	Name	Example	Notes
(none)	Major	C	C E G
m, min, mi, -	Minor	Cm, Cmin, C-	C Eb G
dim, ° , o	Diminished	Cdim, C°	C Eb Gb
aug, +	Augmented	Caug, C+	C E G#
sus2	Suspended 2nd	Csus2	C D G
sus4, sus	Suspended 4th	Csus4	C F G
5	Power chord (no 3rd)	C5	C G

Seventh chords

Symbol	Name	Example	Notes
7	Dominant 7	C7	C E G Bb
maj7, Δ, M7, ma7	Major 7	Cmaj7, CΔ	C E G B
m7, min7, mi7, -7	Minor 7	Cm7	C Eb G Bb
dim7, °7, o7	Diminished 7	Cdim7	C Eb Gb Bbb
m7b5, ø, ø7, min7b5, -7b5	Half-diminished	Cm7b5, Cø	C Eb Gb Bb
mMaj7, mM7, m(maj7), m-maj7	Minor-major 7	CmMaj7	C Eb G B
7sus4, 7sus	Dominant 7 sus4	C7sus4	C F G Bb
7sus4b9, 7b9sus4, 7susb9, 7sus(b9)	Dominant 7 sus4 flat 9	C7sus4b9	C F G Bb Db
7sus2	Dominant 7 sus2	C7sus2	C D G Bb

Extended chords

Symbol	Name	Example	Notes added
9	Dominant 9	C9	+ D
maj9	Major 9	Cmaj9	+ D
m9	Minor 9	Cm9	+ D
11	Dominant 11	C11	+ D F
m11	Minor 11	Cm11	+ D F
13	Dominant 13	C13	+ D A
maj13	Major 13	Cmaj13	+ D A
m13	Minor 13	Cm13	+ D A

Sixth chords and added tones

Symbol	Example	Meaning
6	C6	Major + 6th (no 7th)
m6	Cm6	Minor + 6th
69, 6/9	C69, C6/9	Major + 6th + 9th
m69, m6/9	Cm69	Minor + 6th + 9th
add9, add2	Cadd9	Major triad + 9 (no 7th)
madd9, madd2	Cmadd9	Minor triad + 9
add11, add4	Cadd11	Major triad + 11
7add13, 67	C7add13	7th chord with added 6th/13th (no 9th/11th)

Alterations

Apply to dominant or extended chords:

Symbol	Meaning	Example
b5	Flat 5	C7b5
#5	Sharp 5	C7#5
b9	Flat 9	C7b9
#9	Sharp 9	C7#9
#11	Sharp 11	Cmaj7#11
b13	Flat 13	C7b13
alt, 7alt	Altered dominant (implies b5 #5 b9 #9)	C7alt, Calt

Alterations stack freely: C7#9b13, C13b9#11, Cmaj13#11.

Suspended flat-nine forms can also be written compactly or with parentheses: Csus4b9, Csus4(b9), and Csus(b9) parse as suspended chords with a flat 9; C7sus4b9, C7b9sus4, C7susb9, and C7sus(b9) parse as dominant-suspended flat-nine chords.

Augmented-major chords

All of these work for augmented chords with a major 7th:

Cmaj7#5   CaugMaj7   C+Maj7   C+M7

Parentheses

Parentheses are optional anywhere and are stripped before lookup. Use them for readability when stacking alterations:

C7(#9)       = C7#9
C7(b9)(b13)  = C7b9b13
Cmaj7(#11)   = Cmaj7#11
Cm(add9)     = Cmadd9
Cm7(b5)      = Cm7b5
C(no3)       = C5

Compact and parenthetical forms are fully interchangeable.

Slash chords

Specify any bass note with /:

C/E      // C major with E in bass (1st inversion)
Am/G     // A minor with G in bass
F/G      // F major over G bass
C/Bb     // C major with Bb bass

Slash chords combine freely with everything else: Cm7(b5)/Gb, C7#9/E, Cmaj7(#11)/G.

Equivalent notations

Harmonybeam accepts multiple conventions for the same chord. All of these parse to the same thing:

Cm      = Cmin    = Cmi   = C-       = CMin = CMI
Cmaj7   = CΔ      = CM7   = Cma7
Cm7b5   = Cø      = Cø7   = Cmin7b5  = C-7b5
Cdim7   = C°7     = Co7
Caug    = C+      = CAug  = CAUG
CmMaj7  = Cm(maj7)= Cm-M7 = Cmin-maj7 = Cm/M7
C7#5    = Caug7   = C+7
C13#5   = Caug13  = C+13

What if it doesn’t parse?

If a chord you expect fails:

• Accidentals must be explicit: F# not F sharp, Bb not B flat
• The root must come first: Cmaj7, not maj7C

Additional symbols

Symbol	Meaning	Example
%	Repeat previous chord	C | Am | % | G
r	Rest block	C | r | G

Something missing?

If you’re convinced a chord symbol should parse but doesn’t, or parses incorrectly, we’d like to know. Email us at [email protected] with the symbol and what you expected.