How many semitones is an augmented thirteenth?

A Augmented Thirteenth spans 22 semitones: C – A#. Count the semitones of any interval with the interval calculator.

Is an augmented thirteenth used in practice?

Very rarely. It exists so that notation can express a raised sixth degree voiced above the octave.

What is a compound interval?

Any interval wider than an octave. A Augmented Thirteenth is an octave plus an augmented sixth, and it keeps the character of that simple interval in a more open, less congested form.

How do I play Augmented Thirteenth?

On guitar the handiest shape is Two strings up, A 3 · G 15, read as string and fret; the instrument panel draws it from any starting note with the other shapes. On the piano count 22 semitones up from any key, black keys included. Play the notes together for the harmonic form, one after the other for the melodic form.

What is the inversion of Augmented Thirteenth?

The inversion of Augmented Thirteenth is the Diminished Third: put the lower note an octave higher and the distance that remains is the inversion. The two always add up to an octave, 22 semitones and 2 semitones, and swap their qualities between major and minor, or keep perfect as perfect.

Augmented Thirteenth Interval: How It Sounds, with Song Examples

Play it on your instrument

Loading the keyboard…

From

On the piano, from every note

From	Notes	Play it on your instrument
C	C – A#
C#	C# – A##
D	D – B#
Eb	Eb – C#
E	E – C##
F	F – D#
F#	F# – D##
G	G – E#
Ab	Ab – F#
A	A – F##
Bb	Bb – G#
B	B – G##

Tap a key or a fret to hear it.

Number and quality

An interval has two names. The number counts the letter names from the lower note to the upper one, and the quality counts the semitones inside that number. Augmented Thirteenth spans 13 letter names, which makes it a thirteenth, and 22 semitones, which makes it augmented.

DLetter
ELetter
FLetter
GLetter
ALetter
BLetter
CLetter
DLetter
ELetter
FLetter
GLetter
22 semitones

Read on: number and quality · inversion · compound intervals · consonance and dissonance

Every thirteenth

A thirteenth can take these qualities, one semitone apart; choose one to see the upper note move and hear the pair.

Where it lives

Augmented Thirteenth is in every chord whose formula includes 13A from the root, in every scale that includes it from the tonic, and between these pairs of notes in a major key.

Scales that contain it

C Whole ToneC · D · E · F# · G# · A#

Related intervals

The intervals one step from Augmented Thirteenth: its inversion, the same sound spelled differently, its simple or compound form, and its nearest neighbours in size.

Diminished Third3d · 2 semitones · C – Ebb
Inversion: together they make an octave
Augmented Sixth6A · 10 semitones · C – A#
The simple form, an octave narrower
Major Thirteenth13M · 21 semitones · C – A
One size away
Minor Thirteenth13m · 20 semitones · C – Ab
One size away

Open it in a tool

Understanding Augmented Thirteenth

Names and symbols

Augmented Thirteenth is written A13, 13A: the letter is the quality, the number the size. Chord formulas on this site write the number first, as tonal does.

A compound interval is a simple interval plus an octave, and the two names are used interchangeably in chord symbols: a 9th in a chord is the 2nd of the scale an octave up, an 11th the 4th, a 13th the 6th. The compound name says the note sits above the seventh.

How it sounds

A Augmented Thirteenth spans 22 semitones: C – A#. It is an octave plus an augmented sixth, and compound intervals keep the quality of the simple interval inside them while losing much of its edge — the extra octave gives the two notes room to stop interfering with each other.

It measures the same as a compound minor seventh and exists to preserve the spelling of a raised sixth degree.

How it is used

It is a theoretical interval, met in analysis rather than on a lead sheet.

Learn this properly

Chapter 5: Intervals

Common questions

How many semitones is an augmented thirteenth?: A Augmented Thirteenth spans 22 semitones: C – A#. Count the semitones of any interval with the interval calculator.
Is an augmented thirteenth used in practice?: Very rarely. It exists so that notation can express a raised sixth degree voiced above the octave.
What is a compound interval?: Any interval wider than an octave. A Augmented Thirteenth is an octave plus an augmented sixth, and it keeps the character of that simple interval in a more open, less congested form.
How do I play Augmented Thirteenth?: On guitar the handiest shape is Two strings up, A 3 · G 15, read as string and fret; the instrument panel draws it from any starting note with the other shapes. On the piano count 22 semitones up from any key, black keys included. Play the notes together for the harmonic form, one after the other for the melodic form.
What is the inversion of Augmented Thirteenth?: The inversion of Augmented Thirteenth is the Diminished Third: put the lower note an octave higher and the distance that remains is the inversion. The two always add up to an octave, 22 semitones and 2 semitones, and swap their qualities between major and minor, or keep perfect as perfect.