will explain the theory behind diminished guitar
chords and their function.
There's a lot of confusion around how diminished chords work in
music. I often get asked the question of "when to use them" in a chord
As with music in general, there are no hard and fast rules
(except "if it sounds good, play it!"),
but I'll take you through some of the tried and tested functions
diminished chords can
serve in your music.
Even if you were just looking for a chord
chart (which is further down the page), read through the whole lesson,
split over a few days,
as it will prove very rewarding as far
as developing your improvisation and songwriting skills.
Diminished chord theory - how to construct them
Diminished chords ("diminished" referring to the diminished
5th in the chord) have an
unstable sound. They create an air of tension and unresolve (hear the
examples below) which is what makes them wonderfully intriguing chords
to use in
are 3 main types of diminished chord, as shown in the table below.
Note that if you see
the ° symbol
after the chord letter (e.g. C°), it means "diminished". When
people just use "o" as the proper symbol requires digging out the
As you can see, there's a common occurence of the root
(1), b3 (flat/minor 3rd)
(flat 5th) in the three types. These are the most important tones in
any diminished chord or scale. The flat 5th in relation to a minor 3rd
is what gives it that unstable quality.
So, a diminished triad
can simply be thought of as a minor
chord with a flat
A half diminished
chord is the above diminished
with an added flat 7th.
This chord is also sometimes written as m7b5 (minor 7 flat
5) e.g. Cm7b5.
A diminished seventh
chord is a diminished
triad with an added diminished
That's another way of saying "double flat 7th". So the only difference
between a dim7 and m7b5 chord is the 7th is flattened another semitone
in dim7 chords.
First, just make clear in your mind these
distinctions as each one has a different sound and function which we'll
look at shortly.
Diminished guitar chords chart - how to play them
play along throughout this lesson, here are the most common
diminished guitar chord forms used in chord progressions with their
that I haven't included diminished triads, because these are most
commonly extended to half diminished or diminished 7th. You can see how
the triad exists in both these types.
Half diminished chord chart
Diminished seventh chord chart
Diminished chords function - when to use them
As mentioned earlier, occurences of the diminished triad
are often extended to half diminished or diminished 7th chords,
because they sound more... interesting. Essentially, you're playing the
diminished triad in both those variations anyway, so they're just a
meatier, more colourful version of the triad.
So, whenever there is an occurence of a diminished chord then you
should try both m7b5
(half diminished) or dim7
and go with the one that sounds best to you.
Let's look at some typical uses of the chord.
Leading tone (vii)
a half diminished chord naturally occurs on the 7th degree
(called the leading tone or vii).
In plain English that means whatever the
major tonic (I)
chord is, the diminished chord naturally sits one
down from that.
It's called a "leading tone" or "leading chord"
because it naturally resolves or "leads" to the tonic. You can hear an
example here. See the table
below for a breakdown...
/ Tonic Chord
F / Bdim / C
Dm / Bdim / C
Am / Bdim / C
F# / Cdim / C#
Ebm / Cdim / C#
Bbm / Cdim / C#
C#dim / D
Em / C#dim / D
Bm / C#dim / D
just a few examples. You should be able to see this same leading tone
chord - tonic relationship no matter what key you're in.
In minor keys,
and especially minor keys based around harmonic minor, a
diminished 7th chord is the natural leading tone chord (click to hear
F / Bdim7 / Cm
F# / Cdim7 /
C#dim7 / Dm
Half diminished iii
In major key progressions, the iii
chord (naturally minor) is sometimes replaced with a half
You'll hear this most commonly used in jazz. For