The Diminished chord and the diminished scale are dissonant sounds used to create tension for the purpose of resolution back to a consonant, or harmonious, sound. But there are a number of diminished chords and diminished scales to choose from when looking for some tension in your songwriting.
In this article, I cover all things that are diminished: intervals, chords, scales, and modes. I also have some common diminished guitar chord, scale, and interval shapes, as well as two diminished scale licks.
All Things Diminished: Intervals, Chords, Scales & Modes
When you put the word “diminished” in an article title, people expect to see the word “chord” or “scale” to follow. I’m going to cover both the diminished chord AND the diminished scale, but also everything else that can be considered diminished.
If you are looking to understand the diminished sound in music, then you will have more than enough to learn and practice on guitar, or any instrument. Let’s go from the smallest to the largest: diminished intervals and then the octatonic scale, the diminished scale.
I cover practically every interval type, so if you need to learn or brush up on intervals then read my Music Intervals article. The number “1” below in the various sections is short for either the tonic (T), root note (R) or Perfect Unison (P1).
Diminished intervals (♭5 & ♭♭7)
There are really only 2 diminished intervals: the diminished fifth and the diminished 7th. You may see other diminished intervals, but they are odd enharmonic intervals not worth covering. They are non-practical and rarely seen.
Diminished 5th = d5 = ♭5 = the tritone = 6 semitones \ frets from the root \ tonic note, ex.: B to F
Enharmonic interval equivalent: augmented 4th = A4 = #11, ex,: C to F# (or B to E#)
Resolve tendency for diminished 5th interval, B-F or F-B = C major and F# major
Diminished 7th = d7 = ♭♭7 = 9 semitones \ frets from the root \ tonic, ex.: B to A♭
Enharmonic interval equivalent: major 6th = M6 = 6 or 13, Ex.: B to G#
Resolve tendency for diminished 7th \ major 6th, B-A♭\G# = F# major
The diminished 5th is in all diminished chords and the diminished 7th is ONLY in the fully diminished 7th chord. That’s about it for the diminished intervals, though ere are some guitar shapes of 3 and 4-note diminished 5th \ tritone intervals.
Diminished Chords (dim triad, dim7, m7b5, m9b5, m11b5, & m-maj7b5)
All diminished chords have the diminished triad as the base chord. Let’s look at the chord formulas for all possible diminished chord in the key of B.
1) Diminished triad:
Root note, minor 3rd, diminished 5th = R-m3-d5 = 1-♭3-♭5, ex.: Bdim or Bo = B-D-F
2) Fully diminished seventh chord:
R-m3-d5-d7 = 1-♭3-♭5-♭♭7, ex.: Bdim7 or Bo7 = B-D-F-A♭
The dim7 chord is a symmetrical chord, Bdim7 = Ddim7 = Fdim7 = Ab\G#dim7
3) Half diminished 7th chord:
R-m3-d5-m7 = 1-♭3-♭5-♭7, ex.: Bm7♭5 or Bø7 = B-D-F-A
Bm7♭5 = Dm6
Other diminished chords
4) Minor 9 flat 5, m9♭5 = R-m3-d5-m7-M2 = 1-♭3-♭5-♭7-9, ex.: Bm9♭5 = B-D-F-A-C#
Bm9♭5 = C#7#5♭9
5) Minor 11 flat 5, m11♭5 = R-m3-d5-m7-P4 = 1-♭3-♭5-♭7-11, ex.: Bm11♭5 = B-D-F-A-E
Bm11♭5 = Dm6 add9 = E7sus ♭9
6) Minor major 7 flat 5, m-maj7♭5 or dimMaj7 = R-m3-d5-M7 = 1-♭3-♭5-7, ex.: Bm-maj7♭5 = B-D-F-A#
Bm-maj7♭5 = G7#9, no root
Take a look at my Diminished Triad article for more information on diminished chords, B guitar chord voicings and popular song examples that use the chords.
Diminished Modes & Scales
I’m including all scales and modes that can build at least a diminished triad on the tonic. The standard for diminished scales are the half-whole and whole-half diminished scales, but these are worth checking out.
An oldie but a goodie, everyone should know the 7th mode of the major scale. Let’s keep it simple and only look at the notes, intervals and diminished chords from the B Locrian mode:
Interval abbreviations: m2-m3-P4-d5-m6-m7
Practical intervals names: ♭9, ♭3, 11, ♭5, ♭13, ♭7
The B diminished chords built from the B Locrian scale are Bdim, Bm7♭5 and Bm11♭5.
This mode is built from the second degree of the harmonic minor scale. As the name implies, it is a Locrian scale that has a major 6th as opposed to a minor 6th. Let’s keep with the key of B and look at the A harmonic minor scale starting on the 2nd degree.
Interval abbreviations: m2–m3-P4-d5-M6-m7
Practical intervals names: ♭9-♭3-11-♭5-6/13-♭7
The diminished chords built from the B Locrian M6 mode are the same as B Locrian mode, but also Bdim7.
Dorian #11 & Lydian #9
Because of the dim7 chord built from the Locrian M6 mode, there are 3 other modes from the harmonic minor scale that build dim7, m7♭5, and m-maj7♭5 chords.
The other modes are the Ultra Locrian (next section), Dorian #11 (iv) and Lydian #9 (vi). The 4th and 6th modes are usually used as minor and major scales respectively, but they can also be used over diminished chords.
Dorian #11 builds a dim7, m7♭5, and a m9♭5 chord, while the Lydian #9 builds a dim7 and a m-maj7♭5 chord.
The seventh mode of the harmonic minor is called the Ultra Locrian mode. This diminished mode has one of those “odd” diminished intervals: the diminished 4th. Here is the B Ultra Locrian scale, the 7th mode of the C harmonic minor scale:
Interval abbreviations: m2-m3-d4-d5-m6-d7
Practical intervals names: ♭9-♭3-3-♭5-♭13-♭♭7
You can only build a Bdim and Bdim7 chord using these notes.
If you remember, the dim7 chord is symmetrical where each note in the chord can be the root of another dim7 chord. So if the major 2nd and the major 7th degrees of the harmonic minor scale build a fully diminished seventh chord, then so does the 4th and 6th scale degrees.
The Locrian M2 scale is the 6th mode of the melodic minor scale and it differs from Locrian, Locrian M6 and Ultra Locrian in that it has a major 2nd. Here is B Locrian M2 scale which is the 6th mode of the D melodic minor scale:
Interval abbreviations: M2-m3-P4-d5-m6-m7
Practical intervals names: 9-♭3-11-♭5-♭13-♭7
This diminished mode \ scale builds the same chords as B Locrian but also a Bm9♭5 chord.
Super Locrian (Altered Scale)
This scale \ mode is better known as the Altered Scale and is common in jazz but some blues and rock players will use it as well. It is primarily used over altered 7th chords. Altered 7ths, or 7alt, have some combination of an altered 9th AND altered 5th.
I prefer to think of them as dominant 7th chords with an altered 9th OR an altered 5th, and I’ll throw in #11 and ♭13 chords. But here are the most common chord types of 7alts:
7♭9, 7♭5, 7♭5♭9, 7♭5#9
7#9, 7#5, 7#5#9, 7#5♭9
Here are standard 7♭5 and 7#5 chord voicings. I marked the ♭5 as an alternate Root note for the 7♭5 chords.
Hopefully, you noticed both the ♭5 and #9 / ♭3 intervals which means you can build a diminished triad and a half-diminished 7th chord from this scale but it’s not a go-to scale for diminished chords.
Locrian Pentatonic Scale ( = In Sen Pentatonic ~ the Blues scale)
This scale is one note short of the blues scale. Let’s look at A Locrian Pentatonic which equals the D In Sen Pentatonic
A Locrian Pent Notes: A-C-D-E♭-G
Interval abbreviations: m3-11-d5-m7
Practical intervals names: ♭3-11-♭5-♭7
Chords: Adim, Am7♭5, Am11♭5
Here is the E voicing of the Locrian Pentatonic scale:
So that is just the A Blues scale without E the perfect 5th.
Since this chord equals an m11♭5 chord, then that means you can also build a m6 add9 and a 7sus ♭9 chord. For the A Locrian Pentatonic, you can also build Cm6 add9 and D7sus♭9.
The Blues scale
There isn’t much difference here other than the perfect fifth which makes the scale also good over Am7 and A7 chords.
Interval abbreviations: m3-4/11-d5-P5-m7
Practical intervals names: ♭3-4/11-♭5-5-♭7
Chords: Adim, Am7b5, Am11b5
You can use this scale over the following chords as well: Am7, Am7#11, A7, A7#9, A7#11 (and others)
The Diminished Scale
Well, I’m saving the best for last, or at least THE diminished scale, versus all the other scales that have a diminished sound. This is also the scale most referred to when the octatonic scale (8-note scale) is mentioned. There are two versions of it.
The first is built using alternating whole and half step intervals (WH diminished scale), and the second version is built with or half and whole step intervals (HW diminished scale).
They are both used but with different applications. There are only 3 unique scales pf both types: C, C#\D♭, and D. Since it is a symmetrical scale, scales with tonics of D#\E♭ up to B are repeats of C, C#, and D.
The diminished scale is built using the whole and half steps mentioned below or by adding two dim7 chords separated by either a half-step or whole step.
Half-Whole Diminished Scale
This is the interesting diminished scale if you ask me. It works nicely over dominant 7th chords with or without altered chord tones. Let’s change the key from B to G so that we can use it over for V7 chords in C major.
Interval abbreviations: m2-A2/m3-M3-A4/d5-P5-M6-m7
Practical intervals names: ♭9-#9/♭3-3-#11/♭5-5-6/13-♭7
Alternate scale names: dominant diminished scale, half whole diminished scale, or HW diminished scale
Since it has 8 notes, one of the natural letters has to be repeated and I prefer the ♭9 / #9 combo instead of the ♭3 / 3. That makes more sense to me.
It is used solo over dominant 7th chords especially if they have some combination of ♭9, #9, #11 or 13 extensions. Here is a 1-octave dominant diminished scale in the G voicing:
Here are two G Half-Whole Diminished scale licks in the E & D positions.
Whole-Half Diminished Scale
This version of the diminished scale is used to solo over diminished chords. Here is the scale in B.
Interval abbreviations: M2-m3-P4-d5-m6-d7-M7
Practical intervals names: 9-♭3-11-♭5-♭13-♭♭7-7
Alternate scale names: fully diminished scale, whole-half diminished scale, or WH diminished scale
*Note: This scale has the same notes as the G dominant diminished scale.
I prefer repeating the letters for the diminished 7th and major 7th, though some prefer the ♭5 / #5. That doesn’t make sense to me since you can’t build an augmented chord. Another option is the ♭13 / 13.
It is used solo to over dim triad, dim7, and m-maj7♭5 chords., and it is not as common as the dominant diminished scale.
The phrase “Water, water everywhere – but not a drop to drink” comes to mind. I covered a lot of diminished subjects in this article. Do you practice everything or cherry-pick what you want?
I cherry-pick. I’m not learning more than 1-octave scale positions and licks on the high strings for the dominant diminished and altered scales. The same goes for all the other diminished scales except for the Blues \ Locrian pentatonic scales.
The only diminished chords I use are the dim triad, dim7, and m7♭5 chords and I love using the tritone as a double-stop. Check out the Wikipedia article on the diminished triad if you want some more theory in your head.
I hope you find the diminished sound that you prefer!
All things diminished are covered in this article. I discuss the 2 main diminished intervals, the diminished triad chord, and other diminished chords and various diminished modes and scales The diminished scales and modes are the scales that build diminished chords and that can be used to solo over those chords.