How many semitones is a minor ninth?

A Minor Ninth spans 13 semitones: C – Db. Count the semitones of any interval with the interval calculator.

What is a ♭9 chord?

A dominant seventh with a minor ninth added above the root. The clash is deliberate — it sharpens the pull toward resolution.

What is a compound interval?

Any interval wider than an octave. A Minor Ninth is an octave plus a minor second, and it keeps the character of that simple interval in a more open, less congested form.

How do I play Minor Ninth?

On guitar the handiest shape is Next string, B 1 · E 9, read as string and fret; the instrument panel draws it from any starting note with the other shapes. On the piano count 13 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 Minor Ninth?

The inversion of Minor Ninth is the Major Seventh: put the lower note an octave higher and the distance that remains is the inversion. The two always add up to an octave, 13 semitones and 11 semitones, and swap their qualities between major and minor, or keep perfect as perfect.

Minor Ninth 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 – Db
C#	C# – D
D	D – Eb
Eb	Eb – Fb
E	E – F
F	F – Gb
F#	F# – G
G	G – Ab
Ab	Ab – Bbb
A	A – Bb
Bb	Bb – Cb
B	B – C

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. Minor Ninth spans 9 letter names, which makes it a ninth, and 13 semitones, which makes it minor.

DLetter
ELetter
FLetter
GLetter
ALetter
BLetter
CLetter
13 semitones

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

Every ninth

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

Where it lives

Minor Ninth is in every chord whose formula includes 9m from the root, in every scale that includes it from the tonic, and between these pairs of notes in a major key.

Chords built with it

C7b9C · E · G · Bb · Db
Calt7C · E · Bb · Db

Scales that contain it

C PhrygianC · Db · Eb · F · G · Ab · Bb
C LocrianC · Db · Eb · F · Gb · Ab · Bb
C ChromaticC · Db · D · Eb · E · F · Gb · G · Ab · A · Bb · B
C AlteredC · Db · D# · E · F# · Ab · Bb
C Phrygian DominantC · Db · E · F · G · Ab · Bb
C Half-Whole DiminishedC · Db · Eb · E · F# · G · A · Bb

In C major

E–F
B–C

Related intervals

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

Major Seventh7M · 11 semitones · C – B
Inversion: together they make an octave
Minor Second2m · 1 semitone · C – Db
The simple form, an octave narrower
Octave8P · 12 semitones · C – C
One size away
Major Ninth9M · 14 semitones · C – D
One size away

Open it in a tool

Understanding Minor Ninth

Names and symbols

Minor Ninth is written m9, 9m: 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 Minor Ninth spans 13 semitones: C – Db. It is an octave plus a minor second, 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.

Stretched across an octave, the semitone clash of a minor second becomes a dark, hollow tension rather than a rub.

How it is used

As the ♭9 on a dominant chord it is one of the sharpest colours in jazz harmony, and it is the interval Herrmann built the Psycho strings on. Between two upper voices of a chord an unintended minor ninth is the classic sign of a voicing that needs respacing.

Learn this properly

Chapter 5: Intervals

Common questions

How many semitones is a minor ninth?: A Minor Ninth spans 13 semitones: C – Db. Count the semitones of any interval with the interval calculator.
What is a ♭9 chord?: A dominant seventh with a minor ninth added above the root. The clash is deliberate — it sharpens the pull toward resolution.
What is a compound interval?: Any interval wider than an octave. A Minor Ninth is an octave plus a minor second, and it keeps the character of that simple interval in a more open, less congested form.
How do I play Minor Ninth?: On guitar the handiest shape is Next string, B 1 · E 9, read as string and fret; the instrument panel draws it from any starting note with the other shapes. On the piano count 13 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 Minor Ninth?: The inversion of Minor Ninth is the Major Seventh: put the lower note an octave higher and the distance that remains is the inversion. The two always add up to an octave, 13 semitones and 11 semitones, and swap their qualities between major and minor, or keep perfect as perfect.