In this piano lesson, we will learn how to build an A flat minor chord. While a major chord is formed by combining the root, major third and perfect fifth, a minor chord consists of the root, minor third and perfect fifth.
Difference Between A Flat Major and Minor
The difference between the two types of chords is the third. For a minor chord, the third is a half step lower. For example, the notes of A flat major are Ab-C-Eb, while the notes of A flat minor are Ab-Cb-Eb. Cb is a half step lower than C and is the same as B on your piano keyboard. Instead of playing 1-3-5, for a minor chord, you play 1-b3-5. 
To learn more about this chord and others, check out my course, Piano Chords: How To Form Basic Chords On Piano And Keyboard.
There are many ways to indicate this chord, example, Ab min, Ab mi and Ab#m. Throughout this lesson we shall use them interchangeably and randomly.
Ab Minor Chord Intervals
To form an A flat minor chord, as is the case with every minor chord, you combine a minor third and major third interval. A minor third interval consists of three half steps while a major third interval consists of four half steps.
Locate Ab on your piano. Ab is the second black key in the set of three black keys on your piano. Now move three half steps higher (a distance of a minor third); this will be the key, Cb (B). Now move four half steps higher (a distance of a major third); this will be the key, Eb. Cb is 3 keys to the right of Ab, while Eb is 4 keys to the right of Cb. 
Minor Chord Formula
Minor chords follow the formula R + 3HS + 4HS. This stands for root plus 3 half steps plus four half steps. In other words, to form a minor chord, find its root note then add the note that is 3 half steps (3 keys) higher, then move 4 half steps (4 keys) higher.
Skip Keys to Form Minor chord
Another way to form minor chords like Ab minor is by skipping keys. Place your finger on Ab (the second key in the set of three black keys). Now, skip two keys and play Cb. Then skip three keys and play Eb.
A Flat Minor Chord in Root Position and 1st Inversion and 2nd Inversion
Until now, we’ve looked at the Ab minor chord in its root position, where Ab is the lowest note, Cb is in the middle and Eb is the highest note. Ab-Cb-Eb.
The first inversion of this chord is Cb-Eb-Ab. Ab is played one octave higher and is the highest note in the chord, while Cb is the lowest and Eb is in the middle
As for the second inversion of A flat minor, it’s Eb-Ab-Cb. Eb becomes the lowest note, Ab is in the middle and Cb is the highest. 
Chord Fingerings
Here are possible fingerings for the Ab mi chord. Please note that there is no correct fingering for chords since every hand is not the same. People have different finger lengths and sizes. Also, when playing chords to a song, the fingering depends on what chord comes before and after. But for practice purposes, you can try the following.
In root position, finger 1 (thumb) plays Ab, finger 3 (middle finger) plays Cb and finger 5 (pinky finger) plays Eb. 1-3-5.
For the first inversion, finger 1 plays Cb, finger 2 (index finger) plays Eb and finger 4 (ring finger) plays Ab.
For the second inversion of the Abmi chord, finger 1 plays Eb, finger 3 plays Ab and finger 5 plays Cb.
Video – How to play an Ab minor chord on piano/keyboard
The A flat minor chord occurs naturally in the following keys:
Ab minor (chord i) / Cb major (chord vi)
Eb minor (chord iv) / Gb major (chord ii)
Chords In The Key Of A Flat Minor
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