Chord Symbols

This is not a chord dictionary. Instead, I discuss how chord symbols are constructed, so that you can make your own voicings for chords, or name a chord you just invented.

As opposed to musical notation, there is no universal standard that describes how chord symbols are written. I have tried to be as scientific as the subject allows and keep to the standard that most of my sources seem to agree on.

Unfortunately, no matter if most sources agree, and if I personally manage to be consistent, there will still be plenty of opportunities to be confused. Therefore, it is a good idea to know something about the alternative symbols that do exist. In order to keep the text uncluttered, I have lumped all alternative symbols together at the end of the article.

In order to understand what is presented here, you need to be conversant in interval theory, scale theory and, obviously, chord theory.

The Basics

The purpose of chord symbols is to indicate how the upper notes fall in relation to the root, and to do so with a limited number of characters. This requires many assumptions and leaves things open for ambiguities.

Chord symbols are built on uppercase musical letters—C, F#, Eb etc.—derived from the root note. The upper intervals are indicated by adding letters, numbers and alteration signs to the root note letter in a predetermined fashion.

Chord symbols do not care about key. The upper notes are always analyzed in relation to the root of the chord, and are not affected by key signatures, accidentals, or even other chord members.

Chords are in root position unless otherwise specified, and I will consistently base chord symbol examples on the root note C.

Triads

Basic Triads

The entire system of chord symbols branches out from the symbols for the two most basic chords—the major and minor triads:

If the chord symbol is only an upper-case musical letter, it is assumed to be a major triad. Example: C, G, Ab, F#.
Minor chords are distinguished by the addition of "m": Cm, Gm, Abm, F#m.
Throughout the system, the presence or absence of the "m", with very few exceptions, indicates a major or minor third.
Likewise, unless the fifth is specifically altered, it is assumed to be a perfect fifth.

Altered Triads

Altered intervals are indicated by a plus (+) or sharp (#) sign for raised notes, and a minus (−) or flat (b) sign for lowered notes. The alteration sign is followed by a number indicating the chord member to be altered: 5, 9, 11 or 13.

Since the most commonly altered note is the fifth, the 5 is often omitted, so an orphaned alteration sign is assumed to refer to the fifth.

The two most common altered triads are Cm−5 (diminished) and C+5 (augmented). Their more obscure sisters are Cm+5 and C−5.

Four or More Notes

Four-note or larger chords are triads with added notes. The additions are indicated by adding a number to the chord symbol. Unless altered, this number, with one vital exception, corresponds to the interval as found in the major scale, even if it is a minor chord.

Sixth Chords

Sixth chords by definition always contain a major sixth. The abbreviation for a sixth chord is C6 or Cm6. [1]

Seventh Chords

Seventh chords are indicated with "7" (minor seventh) and "maj7" (major seventh). This is the exception to the rule of using intervals from the major scale.

There are four basic seventh chords: C7, Cm7, Cmaj7 and Cmmaj7:

C7 is pronounced "C seventh" and is formally referred to as a dominant seventh chord. It is a C major triad with an added minor seventh. [2]
Cm7 is pronounced "C minor seventh". It is a C minor triad with an added minor seventh.
Cmaj7 is pronounced "C major seventh". It is a C major triad with an added major seventh. It is important to distinguish between this and the dominant seventh mentioned above.
Cmmaj7 is pronounced "C minor major seventh". It is a C minor triad with an added major seventh.

There are also eight possible altered seventh chords, because the fifth can be either diminished or augmented. The alterations are always stated last in the chord symbol, e.g. C7+5, Cm7−5, etc.

Diminished Seventh

The diminished seventh chord is written Cdim7. Remember that these are symmetrical and contain the same notes as the dim7 chords that is three, six and nine semitones away. Three voicings cover all twelve keys.

Extended Chords

The symbols for the extended chords—C9, C11 and C13—assume the presence of notes that are not explicitly referred to in the symbol:

A ninth chord is an extension of a seventh chord.
An eleventh chord is an extension of a ninth chord.
A thirteenth chord is an extension of an eleventh chord.

Barring alteration symbols, the extension notes are those that occur naturally in the major scale: a major ninth, perfect eleventh and major 13th. If any of these intervening notes are missing, the "add" symbol is used instead (see below).

Since any seventh chord can be extended into a ninth chord, and so on, it is important to note that the "m" and/or "maj" abbreviation that occurs in an extended chord symbol always and exclusively refer to the third and seventh of the chord, respectively. As with three- and four-note chords, the absence of such abbreviations, as always, presumes a major and dominant seventh chord, respectively.

It might be more intuitive to write ninth chords as 7add9, eleventh chords as 7add9add11 and 13th chords as 7add9add11add13. But obviously such a practice would mean that chord symbols no longer serve as abbreviations.

Altered Extended Chords

Altered extended chords are extended chords where any or all of the extension notes, and/or the 5th have been raised or lowered.

These chords have complicated symbols that are not unlike mathematical formulae. The uninitiated might be put off by them, or might express their frustration by simplifying C13+11 into C24 and remaining none the wiser.

With the risk of oversimplifying, these are the most common alterations:

Diminished 5th (−5)
Augmented 5th (+5)
Minor 9th (−9)
Augmented 9th (+9)
Augmented 11th (+11)

Because extended chords get quite crowded, there are a number of alterations that cancel each other out because of enharmonic equivalencies:

Augmented 9th can only appear in major chords, since they are enharmonically equivalent to minor 10ths/3rds.
The 11th cannot be diminished, because this interval is enharmonically equivalent to a major 10th (3rd).
An augmented 11th cannot occur in the same chord as a diminished 5th, because these intervals are also enharmonically equivalent.
Minor 13ths are rare and are equivalent to an augmented 5th.

Alteration signs affect only the immediately following scale degree. All other chord members are assumed to be unaltered. Thus, if several notes are altered, all alterations must be stated individually, e.g. C7+9+11.

In the interest of clarity, altered extension chords are commonly written so that the altered note is separated: C7+9, C9+11, C13+11, etc. Any altered fifth is usually written last; an alteration sign left hanging by itself is, as stated above, assumed to apply to the 5th.

Miscellaneous Chords

Suspended Chords

Suspension is a term from harmony and voice leading and refers to a dissonant non-chordal note that eventually resolves. With chord symbols, suspension always denotes that the third has been replaced by a nearby note. These chords are therefore neither major nor minor.

In chord symbols, suspension is abbreviated "sus". A number is appended, indicating which interval (as found in the major scale) takes the place of the third:

Csus2: root-major second-perfect fifth.
Csus4: root-perfect fourth-perfect fifth.
Csus+4: root-augmented fourth-perfect fifth.

Since it is by far most common to find suspended fourth chords, omitting the number assumes a sus4 chord.

It is also not uncommon to see suspended seventh chords, the symbol for which is C7sus4 (or C7sus).

Chords with Added Notes

The add symbol is used to indicate that one or more of the extension notes have been added to a triad without necessarily filling out the musical space inbetween by stacking thirds. This applies only to 9ths and 11ths, since 13ths are equivalent to sixths, who have their own chord symbol.

Cadd9 is a C major triad with the addition of a (major) ninth. The symbol C9 automatically assumes the presence of a minor seventh as well.
Cadd11 is a C major triad with the addition of a (perfect) 11th. C7add11 is a C11 shape that lacks the ninth.

Some sources use the symbols Cadd2 and Cadd4 where others write Cadd9 and Cadd11, respectively. These are identical for musical purposes. Even though a 9th is an octave above a 2nd, these notes are usually voiced fairly high anyway. As noted in the article on chord voicings, smaller intervals are more effective in the treble.

The following table might be useful to determine when to use "add" or not. Even if it turns out to be quite the opposite, it was still very fun to make!

Component notes							Chord symbol
C	E	G					C
C	E	G	Bb				C7
C	E	G	Bb	D			C9
C	E	G		D			Cadd9
C	E	G	Bb	D	F		C11
C	E	G			F		Cadd11
C	E	G	Bb		F		C7add11
C	E	G		D	F		Cadd9add11
C	E	G	Bb	D	F	A	C13
C	E	G				A	C6
C	E	G	Bb			A	C7/6
C	E	G		D		A	C6•9
C	E	G			F	A	C6add11
C	E	G	Bb	D		A	C9add13
C	E	G	Bb		F	A	C7add11add13

Chords with Subtracted Notes

Chords are frequently simplified in order to provide an easier chord voicing or to ensure good voice leading. Normally, we do not make a lot of fuss about it. However, it might still be good to know the symbol for such a chord should you encounter it on a chord sheet.

If a chord is missing a third or a fifth, a picky transcriber might be thorough as to alert the performer of the omission by writing "no3" or "no5". If any other notes are omitted, alternative methods must be devised.

Suspension/Addition/Subtraction

Having these three tools—"sus", "add" and "no"—at your disposal can give rise to certain ambiguities. When do you use which, and why?

There are a number of very similarly sounding chords that can be abbreviated in wildly differing ways. A C7sus4 can be written C7add11 (no3). A C7sus2 can be written C9 (no3). The difference between sus2 and add2, between sus4 and add4 can sometimes be so subtle as to escape detection. Use the simplest symbol possible that still hints at which intervals, or collisions between intervals that achieve the sound you're after.

13th chords are a good example of this, since they contain seven notes and are thus impossible to fret on a six-string guitar. Hence, a note or two is usually omitted. Realistically, you can simply put C13 or Cmaj13 in your chord sheet and the performer will devise a suitable voicing. If you want to be really thorough and methodical, there are alternative symbols for the ensuing "13-lite" chords. The symbol obviously depends on which notes are left out of it, but common substitutes for full-on 13 chords are 7/6 chords (omitting the 9th and 11th) and C6add9 chords, also C6•9 (omitting the 7th and 11th).

Inverted Chords/Polychords

If another note than the root is the lowest note in the chord, it must be indicated in the chord symbol. The chord symbol is written as usual, the bass note following a slash. C/E means a C major triad with E in the bass.

Normally, this is used to indicate first, second or (for seventh chords) third inversion, but the note does not have to be indigenous to the chord (G/E).

It should also be pointed out that certain chords in inversion are synonyms with other chords—a C6 chord contains the notes C E G A, which also happens to be a first-inversion Am7.

Power Chords and Intervals

Power chords are usually not notated with chord symbols since they are normally found in riff-based music that is best written in tablature or staff notation. But some sources insist on providing symbols for them anyway. When you encounter the symbol C5, it is a power chord that lacks the characteristic third.

This principle can also be put into practice with other intervals that are not straight power chords, for instance C2 for a C–D dyad, or C4 for a C–F dyad. In the context of these chord analyses, sometimes other chord symbols like C6 or C7 have been written to denote intervals rather than the full four-note chords. Similarly, altered power chords use symbols like C−5 and C+5 without requiring the intervening third.

As always, use your ears and play what sounds right.

The Confusion Zone

Triads

The major triad can be hypercorrected to Cmaj. This can be confused with a Cmaj7.
The minor triad can be abbreviated Cmi, Cmin or C−. The latter is especially tricky, since the minus sign is otherwise reserved for alterations (the lack of a number implying an altered 5th).
The diminished triad can be written Cm−, Cdim or C°. (The two latter do not contain the characteristic "m" that denotes a minor third.)
The augmented triad also pops up as Caug, or C+5 can be simplified into C+.

Four-note Chords

Major seventh chords can also be abbreviated CΔ7, possibly simplified into Cmaj.
Minor major seventh chords can be written Cm+7 or CmΔ7.
The symbol Cø7 is supposed to be a "half-diminished" chord, i.e. a diminished triad with a minor 7th. There are no half-diminished intervals, so the proper symbol is the more unambiguous Cm7−5.
Diminished seventh chords can also be encountered as Cdim or C°.
The C7+9 "Jimi Hendrix chord" can sometimes be written C7−10, perhaps to underline the fact that an augmented second is enharmonically equivalent to a minor tenth/third.

1 + 2. This deal with sixth and seventh chords might be illogical at first glance. However, it is only illogical within the framework of chord symbols, where the symbols are built from the root, always use the major scale as benchmark, and take no account of key. If you study where these chord shapes occur in functional harmony, these chord symbols appear much more logical.

Sixth chords are usually encountered as subdominant sixth chords, i.e. based on the fourth scale degree. Apply your knowledge of intervals and scales: F is a fourth above C. D is a sixth above F. D occurs naturally in both C major and C minor.

Similarly, seventh chords are dominant seventh chords, based on the fifth scale degree. G is a fifth above C, F a seventh above G. F occurs naturally in both C major and C minor. [Go back: 1/2]