Chord types and qualities: the complete guide to understanding maj7, m9, add9, 13 and much more

You come across a chord symbol like Cmaj7, Am9, Fm6 or G13 and you know where to put your fingers, but you're not sure exactly what those letters and numbers mean? The answer lies in chord qualities, extensions and alterations — the internal structure that defines the identity, the tension and the movement of each chord.

These symbols are not just different names for shapes on the instrument. They describe the internal structure of the chord: which intervals are present, which notes define its identity, how much tension it produces and what kind of harmonic movement it tends to create.

That is why C, Cmaj7, Cadd9, C6/9 and Cmaj9 start from the same root but do not produce the same feeling. Each one adds a different combination of stability, openness, color and tension.

In this guide, you will understand:

what "chord quality" really means;
how to read symbols like maj7, m9, sus4, add9, 7(b9) and 13;
what the main categories of chords are;
when to use each sound;
why some chords can have the same notes and still get different names;
how to move beyond memorizing shapes and start to understand harmony.

What is chord quality?

The quality describes the main interval structure of a chord in relation to its root.

In C, the letter C indicates the root: C. The absence of any other modifier normally indicates a major triad:

C = C – E – G = 1 – 3 – 5

In Cm, the m tells you the third is minor:

Cm = C – Eb – G = 1 – b3 – 5

Changing just one note transforms the quality of the chord. The major third of C is replaced by the minor third of Cm, changing its identity and how it is perceived.

In everyday use, it is common to call maj7, m7, m9, 6 and 13 "chord types". That works for practical communication. Technically, however, these symbols combine different elements:

a base quality, such as major, minor, augmented or diminished;
a sixth or seventh;
an extension, such as 9, 11 or 13;
an alteration, such as b9, #9, #11 or b13;
an added note, such as add9;
an omission, such as no3 or no5;
a different bass note, as in C/E.

So the most precise term for the whole set is chord qualities and structures.

Is "chord family" the same thing?

Not exactly.

The term chord family is usually used to group chords by functional relationship. In a key, for example, we can speak of:

the tonic family;
the predominant or subdominant family;
the dominant family.

You can also informally say "the C family" to group C, Cm, C7, Cmaj7, C6, Cadd9 and other variations of the same root. But that usage is less precise.

For symbols like maj7, m9, m6 and 13, prefer:

chord quality;
chord type;
chord structure;
quality and extension, when you want to be more specific.

How a chord symbol is built

Most chord symbols can be understood through this structure:

root + base quality + seventh or extension + alterations + bass

Example:

Cmaj9(#11)/E

This symbol tells you:

C: root C;
maj: major structure with a major seventh;
9: extension up to the ninth;
#11: augmented eleventh;
/E: E in the bass.

The theoretical formula is:

1 – 3 – 5 – 7 – 9 – #11

In C:

C – E – G – B – D – F#

In actual performance, not all of these notes need to appear. On a harmony instrument backed by a bass, the fifth can be omitted. The root can also be left to the bass player.

The symbol describes the harmonic identity, while the voicing describes the notes and octaves actually played.

This distinction is essential: a chord and a shape are not the same thing.

Identify Chord — Found a shape on your own fretboard? The app names it back · use it in Chord & Fret

The main categories of chords

There is no universal, closed list containing every possible symbol.

Chord symbols are combinatorial: a base quality can take extensions, alterations, omissions, inversions and different spellings.

Even so, it is possible to organize almost all of the vocabulary used in tonal, modal, popular and jazz music into clear categories.

1. Basic triads

Triads are made up of three notes, generally structured by stacking thirds.

Type	Symbol in C	Formula	Notes	General character
Major	`C`	1–3–5	C–E–G	stable, clear
Minor	`Cm`	1–b3–5	C–Eb–G	introspective, melancholic
Diminished	`Cdim` or `C°`	1–b3–b5	C–Eb–Gb	unstable, tense
Augmented	`Caug` or `C+`	1–3–#5	C–E–G#	suspended, expansive

Major and minor form the center of most tonal repertoire.

The diminished triad is widely used as a passing or approach chord. The augmented triad tends to appear in chromatic movements, altered dominants and dramatic transitions.

2. Suspended chords and power chords

In suspended chords, the third is replaced.

Since the third is the interval that normally determines whether the chord is major or minor, suspension produces a more open sound.

Type	Symbol	Formula	Notes in C	Common use
Suspended 2	`Csus2`	1–2–5	C–D–G	pop, folk, country and intros
Suspended 4	`Csus4`	1–4–5	C–F–G	preparation and resolution to C
Power chord	`C5`	1–5	C–G	rock, riffs and a neutral sound

Csus4 often resolves to C, with the note F descending to E.

That small movement already creates a harmonic narrative: tension and rest.

The power chord has no third. That is why, on its own, it is neither major nor minor.

3. Chords with added notes

The term add indicates that a note has been added without implying a seventh.

Type	Symbol	Formula	Notes in C
Major with added second	`Cadd2`	1–2–3–5	C–D–E–G
Major with added fourth	`Cadd4`	1–3–4–5	C–E–F–G
Major with added ninth	`Cadd9`	1–3–5–9	C–E–G–D
Minor with added ninth	`Cm(add9)`	1–b3–5–9	C–Eb–G–D

The difference between add2 and add9 lies mainly in how the note is understood and distributed.

Both correspond to the pitch class D in a C chord, but 2 suggests a voicing closer to the root, while 9 preserves the idea of a compound extension.

In practice, add9 is one of the best ways to enrich a triad without adding too much tension. It works very well in pop, country, worship, MPB and romantic sertanejo.

Instead of just memorizing Cadd9, look at the relationship between C, E, G and D. The symbol, the formula and the position on the neck tell the same story — when you read them together, the chord stops being an isolated shape.

4. Sixth chords

Sixth chords add the major sixth to the triad.

Type	Symbol	Formula	Notes in C
Major sixth	`C6`	1–3–5–6	C–E–G–A
Minor sixth	`Cm6`	1–b3–5–6	C–Eb–G–A
Major 6/9	`C6/9`	1–3–5–6–9	C–E–G–A–D
Minor 6/9	`Cm6/9`	1–b3–5–6–9	C–Eb–G–A–D

C6 tends to sound warmer and more conclusive than Cmaj7.

C6/9, in turn, combines stability with openness and is widely used in bossa nova, jazz, sophisticated country and romantic arrangements.

Cm6 has a particularly expressive color. It can work as a refined minor tonic, as a passing chord or as a minor subdominant.

A classic movement is:

Cm – Cm(maj7) – Cm7 – Cm6

The inner line descends chromatically:

C – B – Bb – A

This kind of voice leading produces a dramatic feeling without requiring abrupt changes of root.

5. Seventh chords

Sevenths expand the triad and are essential for defining harmonic function and direction.

Type	Symbol	Formula	Notes in C	Tendency
Major seventh	`Cmaj7`, `C7M`, `CΔ7`	1–3–5–7	C–E–G–B	sophisticated tonic
Dominant seventh	`C7`	1–3–5–b7	C–E–G–Bb	tension and resolution
Minor seventh	`Cm7`	1–b3–5–b7	C–Eb–G–Bb	smoothness, predominant
Minor-major seventh	`Cm(maj7)`	1–b3–5–7	C–Eb–G–B	inner tension and dramatic character
Half-diminished	`Cm7(b5)` or `Cø7`	1–b3–b5–b7	C–Eb–Gb–Bb	minor predominant
Diminished seventh	`Cdim7` or `C°7`	1–b3–b5–bb7	C–Eb–Gb–A	symmetrical and highly tense

Maj7 is not the same as 7

This is one of the most important distinctions in chord symbols.

Cmaj7 contains B natural:

C – E – G – B

C7 contains Bb:

C – E – G – Bb

The first can work as a resting chord. The second normally has a dominant character and tends to lead to another chord, such as F.

C7 → F

The third of C7, E, tends to rise to F. The seventh, Bb, tends to fall to A.

This contrary motion explains much of the strength of the dominant resolution.

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6. Extended chords: 9, 11 and 13

After the seventh, the stacking of thirds continues:

9 is the second an octave higher;
11 is the fourth an octave higher;
13 is the sixth an octave higher.

In traditional chord notation, 9, 11 and 13 normally imply the presence of the corresponding seventh.

Type	Symbol	Theoretical formula
Major ninth	`Cmaj9`	1–3–5–7–9
Dominant ninth	`C9`	1–3–5–b7–9
Minor ninth	`Cm9`	1–b3–5–b7–9
Dominant eleventh	`C11`	1–3–5–b7–9–11
Minor eleventh	`Cm11`	1–b3–5–b7–9–11
Dominant thirteenth	`C13`	1–3–5–b7–9–11–13
Major thirteenth	`Cmaj13`	1–3–5–7–9–11–13
Minor thirteenth	`Cm13`	1–b3–5–b7–9–11–13

The symbol does not require playing every note

A complete C13 would have seven notes, but a musician rarely plays them all at once.

In a context with a bass, a C13 voicing may contain only:

Bb – E – A

These notes represent:

b7: Bb;
3: E;
13: A.

The third and the seventh define the dominant function. The thirteenth provides the color.

The root can be played by the bass, and the fifth can be omitted.

This economy is a hallmark of good voice leading. Sophistication does not come from the maximum number of notes, but from choosing the right ones.

Why is Cmaj11 often problematic?

In Cmaj11, the third E and the eleventh F form a semitone interval.

Depending on the register and the voicing, this friction can sound overly clashing.

For that reason, in many contexts you use:

Cmaj9(#11)

The note F is replaced by F#, creating a more open Lydian sound:

C – E – G – B – D – F#

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7. Altered chords

An alteration chromatically modifies a degree of the chord.

The most common alterations are:

b5;
#5;
b9;
#9;
#11;
b13.

Symbol	Essential formula	Typical use
`C7(b9)`	1–3–5–b7–b9	dramatic dominant and resolution to minor
`C7(#9)`	1–3–5–b7–#9	blues, rock, soul and aggressive tension
`C7(#11)`	1–3–5–b7–#11	Lydian dominant and tritone substitution
`C7(b13)`	1–3–5–b7–b13	dark dominant and minor resolution
`C7(#5)`	1–3–#5–b7	augmented dominant
`C7alt`	1–3–b7 with alterations of 5 and 9	open indication of an altered dominant

C7alt does not describe a single fixed collection.

It tells you the dominant should take alterations, usually involving the fifth and the ninth. In a teaching or analytical system, it is better to record the exact alterations whenever they are known.

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8. Inversions and slash chords

The symbol after the slash indicates the lowest note.

C/E

It means a C chord with E in the bass. Since E is the third of C, this is the first inversion.

C/G

It is C with G in the bass, the second inversion.

But not every slash chord is just an inversion:

Gm/C

Here, the Gm triad sits over a C bass. This structure can function as a suspended dominant of C, depending on the context.

Slash chords are very important for:

creating melodic bass lines;
smoothing changes between chords;
producing pedal points;
generating hybrid structures;
enriching progressions without completely changing the upper material.

Example:

C – G/B – Am – Am/G – F

The bass descends:

C – B – A – G – F

The progression feels more continuous because the bass line now has a direction of its own.

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9. Quartal, quintal, cluster and polychord structures

Not every chord is built mainly from thirds.

Quartal chords

They are built by stacking fourths:

C – F – Bb

They produce an open, modal and modern sound. They appear in jazz, film scores, fusion, gospel and contemporary arrangements.

Quintal chords

They are built from fifths:

C – G – D

They sound broad and strong, keeping a relationship with power chords and open textures.

Clusters

They are groupings of adjacent notes, usually in seconds:

C – D – Eb

They can create tension, density or delicacy, depending on the register and the dynamics.

Polychords

They are combinations of two chords perceived simultaneously, such as one triad over another.

They are more common in arrangements, modern jazz, orchestral music and cinematic language.

These constructions should not be confused with conventional qualities like major, minor or dominant. They describe another way of organizing the sound material.

10. Special functional sonorities

Some chord names depend on the key and the function, not just on the absolute notes.

This is the case with:

the Neapolitan chord;
the Italian augmented sixth;
the French augmented sixth;
the German augmented sixth;
the Tristan chord, in analytical contexts.

In C minor, for example, the Neapolitan chord is usually a major triad on the lowered second degree:

Db – F – Ab

Its traditional first-inversion form places F in the bass:

F – Ab – Db

It normally acts as a predominant and leads to the dominant.

It is not a "Neapolitan quality" independent of the key, but a contextual functional interpretation.

How many chord types are there?

The answer depends on what you are counting.

If we count only the base qualities, the set is relatively small. If we include:

extensions;
alterations;
added notes;
omissions;
inversions;
alternate bass notes;
polychords;
equivalent spellings;
post-tonal structures;

then the number grows quickly.

That is why a serious encyclopedia should not treat every possible symbol as an isolated species.

The most consistent model is to:

identify a base structure;
apply operations to the degrees;
record the bass;
preserve the original spelling;
analyze function and context separately.

This way, C7(b9,#11)/E does not need to be stored as a disconnected item.

It can be understood as:

root C;
dominant 7 quality;
lowered ninth;
augmented eleventh;
E in the bass.

This way of thinking also makes learning easier: instead of memorizing hundreds of names, you learn to build and interpret the symbols.

Practical table of the most important chords

The list below covers the most useful core for accompaniment, composition and tonal arranging.

Symbol	Name	Formula	Recurring function or application
`C`	major	1–3–5	tonic, subdominant or dominant depending on the degree
`Cm`	minor	1–b3–5	minor tonic, relative minor or predominant
`C5`	power chord	1–5	riffs and textures without a third
`Csus2`	suspended 2	1–2–5	openness and ambiguity
`Csus4`	suspended 4	1–4–5	preparation for the third
`Cadd9`	major with added ninth	1–3–5–9	enrichment without a seventh
`Cm(add9)`	minor with added ninth	1–b3–5–9	open, emotive minor color
`C6`	major sixth	1–3–5–6	warm tonic, song, choro and country
`Cm6`	minor sixth	1–b3–5–6	refined minor tonic or minor subdominant
`C6/9`	major sixth and ninth	1–3–5–6–9	sophisticated rest
`Cmaj7`	major seventh	1–3–5–7	sophisticated tonic or subdominant
`C7`	dominant seventh	1–3–5–b7	tension that tends to resolve
`Cm7`	minor seventh	1–b3–5–b7	second degree, sixth degree or modal tonic
`Cm(maj7)`	minor-major seventh	1–b3–5–7	dramatic minor tonic
`Cm7(b5)`	half-diminished	1–b3–b5–b7	second degree of the minor mode
`Cdim7`	diminished seventh	1–b3–b5–bb7	approach and symmetrical dominant
`Cmaj9`	major ninth	1–3–5–7–9	sophisticated romanticism
`C9`	dominant ninth	1–3–5–b7–9	blues, funk, choro and a broad dominant
`Cm9`	minor ninth	1–b3–5–b7–9	depth and smoothness
`Cm11`	minor eleventh	1–b3–5–b7–9–11	modal, spacious sound
`C13`	dominant thirteenth	1–3–5–b7–9–11–13	elegant, complete dominant
`Cmaj9(#11)`	major 9 with #11	1–3–5–7–9–#11	Lydian tonic and sophisticated brightness
`C7(b9)`	dominant with b9	1–3–5–b7–b9	drama and strong resolution
`C7(#9)`	dominant with #9	1–3–5–b7–#9	blues, rock and intense tension
`C7(#11)`	dominant with #11	1–3–5–b7–#11	Lydian dominant and chromaticism
`C7(b13)`	dominant with b13	1–3–5–b7–b13	dark resolution, especially to minor
`C/E`	C with E in the bass	chord + bass	inversion and bass line

How to choose which chord to use

There is no rule like "use m9 three times per song".

Its use depends on the context.

The right question is not just "which chord is more sophisticated?", but:

what is this chord's function?
which note is in the melody?
where does the chord come from?
where is it going?
which voice can move by a semitone or a whole tone?
which note is in the bass?
is the arrangement dense or sparse?
which stylistic language are you aiming for?

To enrich a major tonic

Try this progression of increasing complexity:

C → Cadd9 → C6 → Cmaj7 → C6/9 → Cmaj9 → Cmaj9(#11)

This does not mean the last one is always "better".

Each option behaves differently:

C: direct;
Cadd9: open;
C6: warm;
Cmaj7: delicate;
C6/9: stable and broad;
Cmaj9: romantic;
Cmaj9(#11): sophisticated and luminous.

To enrich a minor tonic

Cm → Cm(add9) → Cm7 → Cm6 → Cm9 → Cm11 → Cm(maj9)

Cm(add9) keeps the strength of the triad and adds openness;
Cm7 softens it;
Cm6 creates a refined, ambiguous color;
Cm9 deepens the sound;
Cm11 broadens the modal character;
Cm(maj9) produces strong dramatic tension.

To increase the tension of a dominant

G7 → G9 → G13 → G7(b9) → G7(#9) → G7(b13) → G7alt

The best choice depends especially on the melody and the chord of resolution.

In a resolution to C minor, G7(b9) is particularly effective because Ab, the b9 of G, can descend to G or take part in the chromatic voice leading toward notes of the Cm chord.

To create movement without changing the upper harmony

Use inversions and passing bass notes:

C – C/B – Am7 – Am7/G – Fmaj7

The ear perceives a descending line even when part of the harmonic material is preserved.

Example of a romantic, dramatic and sophisticated progression

Consider:

Cmaj9 – E7(b9)/G# – Am9 – Gm9 – C13 – Fmaj9 – Fm6 – C/G – A7(b9) – Dm9 – G13 – C6/9

Cmaj9

Establishes a romantic major tonic.

The major seventh and the ninth expand the triad without removing its resting character.

E7(b9)/G#

Works as a secondary dominant of Am.

The G# in the bass creates an ascending approach to A. The b9 intensifies the drama.

Am9

Receives the resolution smoothly.

The ninth B can be kept as a common tone or inner line.

Gm9 – C13

Forms a ii–V preparation toward F.

It is a temporary tonicization of the fourth degree.

Fmaj9

Produces lyrical expansion.

Next, Fm6 turns the major fourth degree into a borrowed minor subdominant.

Fm6

The note Ab introduces the modal interchange.

In the passage from Fmaj9 to Fm6, A can descend to Ab, while E can descend to D, the major sixth of the minor chord.

These chromatic and diatonic lines produce an expressive change without breaking the continuity.

C/G

Returns to the tonic with G in the bass, keeping a sense of movement and avoiding an early full conclusion.

A7(b9) – Dm9

A7(b9) acts as a secondary dominant of Dm9.

G13 – C6/9

G13 creates a rich dominant that is not overly aggressive.

C6/9 concludes with stability, warmth and openness.

The result does not depend only on the names. The unity comes from the inner lines, the common tones and the semitone resolutions.

When studying a progression like this, play each chord on its own, then follow just the bass, and finally watch a single inner voice. This process turns a sequence of chord symbols into harmonic understanding.

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Can chords with the same notes have different names?

Yes.

C6 contains:

C – E – G – A

Am7/C also contains:

C – E – G – A

The notes are the same, but the interpretation can change.

If C is perceived as the root and the chord functions as a major tonic with a sixth, the name C6 is appropriate.

If A is perceived as the root and C is only in the bass, Am7/C may be more informative.

Another example:

Cm6 = C – Eb – G – AAm7(b5)/C = C – Eb – G – A

The choice depends on:

the perceived root;
the bass;
the key;
the preceding and following chord;
voice leading;
harmonic function;
melodic spelling.

So recognizing the notes does not settle the analysis. The context defines the most useful name.

Which notes can be omitted?

The answer varies with the chord and the arrangement.

In general:

the perfect fifth is often the first candidate for omission;
the root can be omitted when it is clearly present in the bass;
the third and the seventh are essential in dominant chords;
extensions chosen as color should remain;
an explicitly indicated alteration should not disappear without reason;
problematic notes, such as the perfect 11 in a maj11, can be omitted or replaced by #11 depending on the intention.

In G13, a pianist can play B–F–E, while the bass player plays G.

The chord remains clearly dominant because B and F form the defining tritone, and E provides the thirteenth.

How much should you use sophisticated chords?

Use enough to expand the expression, not to hide the music.

A harmony can seem sophisticated with just a few well-handled devices:

an inversion creating a singable bass;
a major seventh sustained in the melody;
a secondary dominant before an important chord;
a borrowed minor subdominant;
a ninth held as a common tone;
an inner chromatic line;
a well-prepared altered resolution.

Adding extensions to every chord can reduce contrast. If everything has maximum density, no sound stands out.

An efficient strategy is to create levels:

keep some chords simple;
choose structural points for extensions;
concentrate alterations on the dominants;
use inversions to lead the bass;
preserve common tones;
check whether the melody accepts the extension.

The melody always takes priority.

A C6 contains A natural. If the melody sustains Ab, there will be a conflict — which can be expressive or inappropriate, depending on the intention.

How to study chord qualities without just memorizing

For each chord type, study six dimensions.

1. Formula

m9 = 1 – b3 – 5 – b7 – 9

2. Notes on a known root

In C:

Cm9 = C – Eb – G – Bb – D

3. Sound

Compare Cm, Cm7, Cm9 and Cm11 without changing the bass.

4. Function

Find out when the chord works as a tonic, predominant, dominant, modal interchange or passing chord.

5. Voice leading

Notice which notes stay and which move to the next chord.

6. Voicings on the instrument

Play more than one position.

The same chord can sound close, open, low, bright, dense or transparent.

Learning becomes more solid when symbol, formula, listening and playing are studied together.

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Most common equivalent notations

Chord symbols are not fully standardized. The same chord can appear with different symbols.

Forms found	Meaning
`Cm`, `Cmin`, `C-`	C minor
`Cmaj7`, `CM7`, `C7M`, `CΔ7`	C major seventh
`Cm7(b5)`, `Cø7`	C half-diminished
`Cdim7`, `C°7`	C diminished seventh
`Caug`, `C+`	C augmented
`C7(#5)`, `C+7`, `Caug7`	dominant with augmented fifth
`Csus`, `Csus4`	suspended 4, by convention

A good chord-symbol reader should recognize aliases, but a publication or app should choose one main convention and apply it consistently.

In Brazil, 7M is quite common. In international materials, maj7 tends to be more explicit and interoperable.

A balanced solution is to accept both and display the convention chosen by the user.

Frequently asked questions

Are maj7, m9 and m6 chord families?

The more precise term is chord qualities or types. m9 also involves an extension, and m6 involves a sixth added to the minor structure. "Family" usually refers to harmonic function or an informal grouping.

What is the difference between Cadd9 and C9?

Cadd9 is a major triad with an added ninth (C – E – G – D). C9 is a dominant chord with a minor seventh and a ninth (C – E – G – Bb – D). The presence of Bb completely changes the function.

What is the difference between C6 and C13?

C6 is a major triad with a sixth (1 – 3 – 5 – 6). C13, with no other qualifier, is an extended dominant chord (1 – 3 – 5 – b7 – 9 – 11 – 13). In practice, several notes can be omitted, but the minor seventh remains part of its dominant identity.

Is C7 major or minor?

The inner triad is major, but the seventh is minor. That is why C7 is called a dominant seventh, or major-minor, chord (1 – 3 – 5 – b7).

Can I omit the fifth?

Often, yes. In many chords with a seventh or extensions, the perfect fifth adds little information. Omitting it frees up room for more characteristic notes, such as 7, 9, 11, 13 or alterations.

Are add2 and add9 the same thing?

They can use the same pitch class, but they are not necessarily equivalent in notation and voicing. add2 suggests the second close to the root; add9 suggests the same note as a compound extension. In a rigorous system, the spelling should be preserved.

Is there a complete list of all chords?

There is a finite set of pitch-class combinations in the twelve-note system, but the names and interpretations do not form a simple, universal list. Symbols can be generated from base quality, extensions, alterations, omissions, bass notes and functional context.

Which chord sounds most romantic and sophisticated?

Some common options are maj7, maj9, 6/9, m9 and m6. The result depends on the voicing, the melody and the progression. On its own, no symbol guarantees a specific emotion.

Which chord creates the most drama?

m(maj7), 7(b9), 7(b13), diminished chords, minor subdominants and augmented chords can create drama. The resolution and voice leading matter more than the name alone.

A smarter way to see chords

Chords are not a collection of independent shapes.

They are structures formed by interval relationships.

When you understand that:

maj7 adds a major seventh;
m9 combines a minor structure with a minor seventh and a ninth;
add9 adds the ninth without including the seventh;
13 implies an extended dominant;
the slash defines the bass;
alterations modify specific degrees;

you start to decode new chords even without having memorized them before.

This is the leap from knowing a shape to understanding harmony.

Want to change keys without redoing any of this? In the Chord & Fret app you drag and the whole neck rewrites itself — App Store and Google Play.

Conclusion

The terms maj7, m9, m6, add9, 13, sus4 and alt are part of an organized system.

They tell you how a base structure has been expanded, altered or redistributed.

To master this vocabulary, you do not need to memorize every possible combination.

The most efficient path is to learn:

the base qualities;
the interval formulas;
the extension rules;
the most common alterations;
the difference between symbol and voicing;
the function of each chord in the progression;
voice leading.

From there, complex chords stop looking like arbitrary codes. They become understandable variations of structures you already know.

The next time Cmaj9(#11)/E appears, you will not just see a long name. You will see a root, a quality, extensions, an alteration, a bass and several possibilities for musical voice leading.

Sources and editorial methodology

This guide was structured from an analytical review of chord representation standards, harmony literature, chord-symbol systems, computational analysis and musical corpora.

The methodology separates symbol, interval structure, function, voicing and context to avoid mixing chord qualities with other analytical categories.

See also: Beautiful chords — beautiful guitar shapes to play these chords.

Updated July 9, 2026