Many of the extended chord names are just additions or changes to the basic 7th, 11th and 13 chords. Here we look at chords with #5, b5, #9, b9 and #11 extensions, which probably covers all the variations we will ever come across.

#5 and b5 variations of chords

If you find this article useful, you will like The Chord Code.

Find the chord part without the #5 or b5.

To get the #5 version of the chord, sharpen the 5th.

To get the b5 version, flatten the 5th.

maj7 #5

Start with the major 7th chord: root – maj 3rd – 5th – maj 7th

Sharpen the 5th note to get the maj7#5 chord: root – maj 3rd – #5 – maj 7th

maj 7 b5

Start with the major 7th chord: root – maj 3rd – 5th – maj 7th

Flatten the 5th note to get the maj 7b5 chord: root – maj 3rd – b5 – maj 7th

min 7 b5

Start with the minor 7th chord: root – min 3rd – 5th – min 7th

Flatten the 5th note to get min7b5: root – min 3rd – b5 – min 7th

This chord is also called the half diminished 7th.

min 7 #5

Start with the minor 7th chord: root – min 3rd – 5th – min 7th

Sharpen the 5th note to get the m7#5 chord: root – min 3rd – #5 – min 7th

7b5

Start with the 7th chord: : root – maj 3rd – 5th – min 7th

Flatten the 5th note to get the 7b5 chord: root – maj 3rd – b5 – min 7th

7#5

Start with the 7th chord: : root – maj 3rd – 5th – min 7th

Sharpen the 5th note to get the 7#5 chord: root – maj 3rd – #5 – min 7th

Similarly we can make 9th chords with b5 and #5 notes. Starting with the appropriate chord and making the needed change, find notes of m9b5, min maj 9th #5, major 9 b5, min9#5 etc.

b9 and #9 variations

b9 note is the note just before the 9th note.

·         Major 2nd note is the 9th note.

·         Minor 2nd note will be the b9 note.

The b9 note is the note just after the root. [root – minor 2nd – major 2nd … Minor 2nd note is same as the b9 note].

#9 note is the note just after the 9th (major 2nd) note. It is same as the minor 3rd note.

7 b9

Start with the 7th chord: root – major 3rd – fifth – minor 7th

Add the b9 note to the chord: root – major 3rd – fifth – minor 7th – b9

Example: the G7 b9 chord

G7 chord has the notes: G B D F

The 9th note of G is same as the major 2nd note of G, which is A. flat 9th note is flat of A: Ab

G7 b9 will have the notes: G B D F Ab

Similarly adding #9 to the 7th chord gives the 7 #9 chord. For example, the G7#9 chord will have the notes: G B D F A#

Variations of 7, 11, 13 chords with #9 and b9

Adding or changing b9 and #9 to the dominant 11th and 13th chords gives 11 b9, 13 b9, 11 #9, 13 #9 etc.

A chord name like ‘minor 13b9’ or ‘major11#9’ suggests we start from the appropriate 13th or 11th chord.

The terms ‘Minor major’, ‘minor’, ‘major’ and ‘dominant’ point to the correct use of the major 3rd, minor 3rd, minor 7th and major 7th notes.

Example: Minmaj13#9 chord

Start with the minor major 13th chord: root – minor 3rd – 5th – major 7th – 9th – 11th – 13th

Change the 9th note to a #9 note to get the minor major 13#9 chord: root – major 3rd – 5th – minor 7th – #9th – 11th – 13th

Example: Maj11b9 chord

Start with the minor major 13th chord: root – major 3rd – 5th – major 7th – 9th – 11th

Change the 9th note to a #9 note to get the minor major 11b9 chord: root – major 3rd – 5th – major 7th – b9th – 11th

Chords with both b5 / #5 and b9 / #9 variations

To get the b5 or #5 variation of a chord, start with the part of the chord with the b5 or #5, then change the 5th note to a flat 5 or sharp 5 note.

To get the b9 or #9 variations of a chord, add the b9 or #9 note to the chord.

We can have chords with both these variations. See the following examples.

7b5b9

Start with the 7th chord: root – major 3rd – 5th – minor 7th

Change the 5th note to a flat 5th note

Add the b9 note.

7b5b9 chord: root- major 3rd – b5th – minor 7th – b9 (minor 2nd note)

For example, the G7b5b9 chord:

G7 chord: G B D F

G7b5 chord: G B Db F

G7b5b9 chord: G B Db F Ab   (Ab note is the b9 note of G – the note immediately next to G)

Similarly by adding the appropriate b5 / #5 and b9 or #9 notes, we can find the chords 7b5#9, 7#5b9 or 7#5#9

For example, G7b5#9 chord: G B Db F A#   (A# note is the #9 note of G – the note immediately next to A, the major 2nd or 9th note)

#11 variations

The #11 note is the sharp fourth note. The note immediately next to the perfect 4th note (the note used in sus 4th chords), which is same as the note just before the fifth note.

Though b5 and #11 notes are the same,

  • b5 refers to changing the 5th note in the chord to a flattened fifth
  • whereas #11 means adding the #4th note to the existing chord. When the chord already has a 11th note in it, #11th means sharpening the 11th note.

13 #11

Start with the 13th chord: root – major 3rd – 5th – minor 7th – 9th – 11th – 13th

Change the 11th note to a #11th note.

Example G13 #11 chord

G13 chord: G B(major 3rd) D(5th) F(minor 7th) A(9th) C(11th) E(13th)

G13#11 chord: G B(major 3rd) D(5th) F(minor 7th) A(9th) C#(#11th) E(13th)

By using the major or minor 3rd and 7th appropriately, we get the major 13#11,  minor major 13th #11 and minor 13th #11 chords. 

e.g. GM13 #11 chord: G B(major 3rd) D(5th) F#(major 7th) A(9th) C#(#11th) E(13th)

Similarly, from any chord (7, 9, 11, 13 or other), to get the #11 version, just add a #11th note to the basic chord or change an already existing 11th note to a #11.

Become confident with chords. Understand chords thoroughly using the chord code.