What Is an Augmented-Major 7th Chord?
An augmented-major 7th chord is an augmented triad with a major 7th added above the root. It combines the floating, eerie quality of an augmented triad with the luminous shimmer of a major 7th — creating one of the most distinctive and unusual sounds in harmony.
Written as Cmaj7#5, this chord appears naturally on the III degree of the melodic minor scale, making it a key colour in jazz minor harmony.
How to Build an Augmented-Major 7th Chord
Formula
Root + Major 3rd + Augmented 5th + Major 7th
Semitones: 0 — 4 — 8 — 11
Example: C Augmented-Major 7th
- C (root)
- E (4 semitones = major third)
- G# (8 semitones = augmented fifth)
- B (11 semitones = major seventh)
vs. Major 7th: Cmaj7 = C E G B. Cmaj7#5 = C E G# B. The raised 5th is the only difference — but it dramatically changes the flavour from dreamy to ethereal and unmoored.
All 12 Augmented-Major 7th Chords
| Chord | Root | Major 3rd | Aug. 5th | Major 7th |
|---|---|---|---|---|
| Cmaj7#5 | C | E | G# | B |
| Gmaj7#5 | G | B | D# | F# |
| Dmaj7#5 | D | F# | A# | C# |
| Amaj7#5 | A | C# | E# | G# |
| Emaj7#5 | E | G# | B# | D# |
| Bmaj7#5 | B | D# | Fx | A# |
| F#maj7#5 | F# | A# | Cx | E# |
| Fmaj7#5 | F | A | C# | E |
| B♭maj7#5 | B♭ | D | F# | A |
| E♭maj7#5 | E♭ | G | B | D |
| A♭maj7#5 | A♭ | C | E | G |
| D♭maj7#5 | D♭ | F | A | C |
The Sound of an Augmented-Major 7th Chord
Ethereal, luminous, floating, otherworldly, tense but beautiful.
This chord sounds like a major 7th chord that has lost its gravitational anchor. The augmented 5th pulls the top of the chord upward while the major 7th adds shimmer. The result is a chord that sounds suspended between worlds — beautiful but unsettled.
You hear this sound in impressionist music (Ravel, Debussy), in post-bop jazz, and in contemporary film scoring when composers want something luminous but uncertain.
Augmented-Major 7th in Melodic Minor
The augmented-major 7th appears naturally on the III degree of the melodic minor scale:
C Melodic Minor scale: C D E♭ F G A B
III chord: E♭ G B D = E♭maj7#5 (augmented-major 7th)
Jazz players use this in minor key harmony for its distinctive colour.
How to Use Augmented-Major 7th Chords
1. As a colour chord: Use Cmaj7#5 in place of Cmaj7 for a more ethereal, impressionistic quality.
2. In melodic minor harmony: Jazz musicians use this chord as the IIImaj7#5 in minor key progressions.
3. In impressionist music: This chord fits naturally in Ravel/Debussy-style writing where ambiguous, floating harmonies are the goal.
4. As a transition: Move from Cmaj7 to Cmaj7#5 by raising the 5th a semitone — creates a subtle upward motion within a static chord.
Free: Chord Ear Training Cheat Sheet
Train your ear to distinguish the ethereal quality of the augmented-major 7th from standard major 7th chords.