Tritone Substitution on Guitar: A Practical Guide for Chord Players

The tritone substitution is the most powerful single chord substitution in jazz harmony. It sounds complex, but the rule is simple: any dominant 7th chord can be replaced by the dominant 7th chord a tritone (6 half steps) away. That’s it.

Why does it work? Because two dominant 7th chords a tritone apart share the same two most important notes - the 3rd and the 7th - just inverted. The “guide tones” that define the dominant chord’s tension and resolution are identical in both chords. The bass note changes dramatically, creating that characteristic chromatic voice leading.

What Is a Tritone?

A tritone is exactly half an octave - 6 half steps. From G, the tritone is Db (or C#). From C, it’s F# (or Gb). From D, it’s Ab.

Every note has exactly one tritone partner. The tritone is a symmetrical interval - the tritone of a tritone is the original note.

Finding the tritone quickly on guitar: Start at any note. Move up or down 6 frets on the same string. That’s the tritone. Or go across to the same fret on the opposite side of the neck (roughly).

Why the Tritone Sub Works

In a G7 chord, the defining notes are:

B (the major 3rd of G)
F (the minor 7th of G)

The tritone of G7 is Db7. In Db7:

F is the major 3rd of Db
Cb (enharmonic B) is the minor 7th of Db

The 3rd and 7th are identical - just swapped. B becomes the 7th, F becomes the 3rd. Same notes, same harmonic tension. The resolution to C major works from either G7 (a 5th above) or Db7 (a half step above, creating smooth chromatic voice leading).

The Tritone Sub in Action: ii-V-I

The most common application is replacing the V chord in a ii-V-I progression.

Normal ii-V-I in C: Dm7 - G7 - Cmaj7

With tritone sub: Dm7 - Db7 - Cmaj7

The Db7 is the tritone sub for G7. Notice how the bass line descends by half step: D - Db - C. That smooth chromatic bass movement is exactly why the tritone sub sounds so satisfying - it creates a half-step approach to the tonic.

Chord voicings on guitar:

G7 (before substitution):

e|---1---|
B|---0---|
G|---0---|
D|---0---|
A|---2---|
E|---3---|

Db7 (tritone substitution):

e|---4---|
B|---4---|
G|---4---|
D|---4---|
A|---4---|
E|---4---|

Or a cleaner Db7 voicing (shell):

e|---x---|
B|---6---|
G|---6---|
D|---7---|
A|---4---|
E|---x---|

More Applications

Substituting the V7 in Blues

In a 12-bar blues in A, bar 12 (the V chord, E7) can be replaced with Bb7:

E7: x 7 6 7 5 x
Bb7: x 1 0 1 3 x

The Bb7 creates a half-step approach to A7 (the I chord at bar 1). This is extremely common in jazz blues.

Creating Chromatic Chord Movement

In any progression where you have a dominant chord resolving down a 4th (or up a 5th), you can substitute the tritone sub and create half-step resolution instead.

Before: F7 - Bb maj7 (down a 4th, functional V-I) After: B7 - Bbmaj7 (half-step approach, tritone sub)

The B7 is the tritone of F7. The half-step drop from B to Bb sounds bold and modern.

Double Tritone Sub (Duke Ellington Move)

Replace both the ii and the V with their tritone subs:

Normal: Dm7 - G7 - Cmaj7 Double sub: Ab m7 - Db7 - Cmaj7

This creates a chain of descending half steps in the bass: Ab - Db - C. Ultra-smooth chromatic voice leading that sounds sophisticated even when played simply.

How to Find Any Tritone Sub Quickly

Find the root of the dominant chord you want to substitute.
Count up 6 frets on any string (or down 6 frets).
That’s your tritone sub root.
Play that note as a dominant 7th chord.

From D7: count up 6 frets from D = Ab. So Ab7 is the tritone sub for D7.
From A7: count up 6 frets from A = Eb. So Eb7 is the tritone sub for A7.

Voicings That Work Well for Tritone Subs

Because the tritone sub often creates half-step voice leading, shell voicings and three-note voicings tend to work better than full 6-string chords. They’re more mobile and let the bass notes breathe.

A useful moveable dominant 7th shell voicing (root on 5th string):

e|---x---|
B|---3---|
G|---3---|
D|---4---|
A|---3---|
E|---x---|

Move this shape to any root on the A string to get any dominant 7th in a compact, moveable form.

Try This in Guitar Wiz

Tritone substitution is about knowing your dominant 7th chords deeply - their voicings, their root positions, and their guide tones. Guitar Wiz’s Chord Library is perfect for this exploration. Look up any dominant 7th chord and cycle through its different positions on the fretboard.

Then find its tritone sub: if you looked up G7, now look up Db7. Compare the voicings side by side. You’ll see how the guide tones (3rd and 7th) appear in both chords.

Build a ii-V-I progression in the Song Maker and practice swapping in tritone substitutions on the V chord. Use Guitar Wiz’s chord diagrams to find clean, guitaristic voicings for the substitute chords - especially chords that you wouldn’t normally play (like Db7 or Ab7).

Download Guitar Wiz on the App Store · Explore the Chord Library →

FAQ

Is tritone substitution only for jazz?

It originated in jazz but appears in pop, R&B, and film music. Any time you hear a chord resolving by half step to the next chord, there’s a good chance a tritone sub is involved.

Do I need advanced theory to use tritone subs?

You need to be comfortable with dominant 7th chords and understand the ii-V-I progression. Beyond that, the rule is simple: count 6 half steps and substitute.

Can I tritone substitute minor chords?

Technically you can, but the tritone sub classically applies to dominant 7th (V) chords because of the shared guide tones. Minor chord substitution works differently.