The A#maj9 piano chord is a major 9th chord with the notes A#, D, F, A, C. On piano it is played from the keys A#, D, F, A, C, root position first, then in inversions. Whether you are learning it for the first time or checking a voicing, this page has the notes, the piano fingerings, the inversions and alternatives, and the progressions it appears in.
What notes are in the A#maj9 chord?
The A#maj9 chord is a major 9th chord, and its notes are fixed: A#, D, F, A, C. Every voicing on every instrument uses these same notes, in some order and in some octave — change one of them and you are playing a different chord. The table below lists each note with its interval from the root A#, so you can see the structure of A#maj9 at a glance. On the piano, the root-position keys A#, D, F, A, C show A#maj9 most clearly.
| Note | Interval |
|---|---|
| A# | Root |
| D | 3 |
| F | 5 |
| A | 7 |
| C | 9 |
The root is A#, the note the chord is named after and the note your ear hears as home. Above it, the intervals in A#maj9 are 3, 5, 7, 9. Learn those intervals rather than memorising the shape alone, because the same interval pattern transposed to another root gives you the same quality of chord anywhere. On the piano, the notes appear in the order the fingering dictates, but the set of notes never changes.
A#maj9 sounds smooth and spacious, the sound of jazz ballads, neo-soul and soft pop. That character comes straight from the intervals above, not from the instrument: the same notes on piano, guitar or ukulele carry the same colour, even though the voicing changes. On the piano, play the keys A#, D, F, A, C slowly and listen for each note of A#maj9 in turn.
Comparing A#maj9 with its closest relatives helps to fix it in your ear. In short, major 9th against dominant 9th: A#maj9 keeps the major 7th A; the dominant 9th flattens it to G#. The major 9th sounds dreamy; the dominant 9th sounds bluesy. Hearing the comparison matters more than reading it: play A#maj9, then play the chord it is compared with above, and let your ear find the note that changed. On the piano, A#maj9 is the keys A#, D, F, A, C, and the inversions above move the same notes around.
How to play A#maj9 on piano
On the piano, A#maj9 is played from the keys A#, D, F, A, C. In root position the lowest note is A#, the root, with the other notes stacked above it in the order A#, D, F, A, C. Play it with the right hand first, then with the left hand an octave lower, so both hands know the shape of A#maj9 before you try it in a progression.
First inversion of A#maj9 puts D in the bass, with the notes in the order D, F, A, C, A#. The chord is still A#maj9 — the notes have not changed, only their order — but the bass note changes how it connects to the chord before and after it. Use this inversion when the bass line wants to step to D rather than jump to A#, and practise moving from root position to this inversion without lifting your hand off the keys more than you must.
Second inversion of A#maj9 puts F in the bass, with the notes in the order F, A, C, A#, D. The chord is still A#maj9 — the notes have not changed, only their order — but the bass note changes how it connects to the chord before and after it. Use this inversion when the bass line wants to step to F rather than jump to A#, and practise moving from root position to this inversion without lifting your hand off the keys more than you must.
Third inversion of A#maj9 puts A in the bass, with the notes in the order A, C, A#, D, F. The chord is still A#maj9 — the notes have not changed, only their order — but the bass note changes how it connects to the chord before and after it. Use this inversion when the bass line wants to step to A rather than jump to A#, and practise moving from root position to this inversion without lifting your hand off the keys more than you must.
Because A#maj9 has 5 notes, it has further inversions beyond the third, each one putting a different chord tone in the bass. The principle stays the same: the notes are always A#, D, F, A, C, and the inversion you choose is the one whose bass note makes the smoothest line through the progression. Try the Chord Inverter to see every inversion of A#maj9 on the keyboard.
For fingering, a good starting point for A#maj9 in root position in the right hand is thumb on A#, then one finger per note in order, with the little finger on the top note C. For the left hand, mirror it: little finger on the low A# and thumb on the top note. When a note is a black key — A# — let your longer fingers take it, since they reach the black keys more easily. Practise A#maj9 in root position and first inversion, hands separately, then together, at a slow tempo, and use the Piano Chord Finder to check the voicing on the keyboard.
Common mistakes
These are the mistakes that most often make A#maj9 sound wrong on the piano, and each one has a concrete fix. Work through them one at a time rather than trying to fix everything at once.
Forgetting the 9th. Without C this is just a major 7th chord. The 9th is the note that makes it a 9th. On the piano, A#maj9 is the keys A#, D, F, A, C, and the inversions above move the same notes around.
Playing every inversion with the same hand shape. Each inversion of A#maj9 needs its own hand shape, because the notes sit under different fingers. If you force the root-position fingering onto an inversion, the hand cramps and notes get missed. Learn the fingering for each inversion of A#maj9 separately, hands apart, before you join them. On the piano, A#maj9 is the keys A#, D, F, A, C, and the inversions above move the same notes around.
Flattening the 7th. If the 7th is G# instead of A, the chord becomes a dominant 9th with a different function. Keep the 7th major. On the piano, play the keys A#, D, F, A, C slowly and listen for each note of A#maj9 in turn.
Crowding five notes. Five notes need space. Drop the 5th (F) and spread the rest across octaves so the 9th C can ring. On the piano, A#maj9 is the keys A#, D, F, A, C, and the inversions above move the same notes around.
Where A#maj9 is used
A#maj9 is not a diatonic triad in any major or minor key, because it is an extended or altered chord, but its base triad belongs to the key of D# major, the key of F major, the key of A# major. a tonic chord in jazz and neo-soul, where the 9th adds width without tension. As a dominant-type chord it also points toward D# major, the key a perfect fourth above A#, which is the tonic it most often resolves to. That is where A#maj9 does its work: not as a home chord, but as a chord that creates movement and then resolves. On the piano, the root-position keys A#, D, F, A, C show A#maj9 most clearly.
Because A#maj9 is an extended or altered chord, it appears in progressions as a colour or a dominant rather than as a diatonic staple. Try it in place of the plain A# triad in a progression you already know, and listen to how the extra notes change the feel — that substitution is the usual way extended chords enter real music. The Chord Progression Builder lets you try A#maj9 in a progression in any key and hear how it connects to the chords around it. On the piano, A#maj9 is the keys A#, D, F, A, C, and the inversions above move the same notes around.
The same chord on other instruments is covered in A#maj9 on guitar, A#maj9 on ukulele, A#maj9 on bass, and the scales that fit over it are the A# major scale and the A# minor pentatonic scale. Learning A#maj9 on the piano and then checking it on another instrument is one of the best ways to fix the notes — A#, D, F, A, C — in your memory, because the notes stay the same while everything else changes.
Practising A#maj9
A short worked example makes A#maj9 concrete. Play the four-chord progression D# – A# – Cm – G# in D# major, the key A#maj9 most often resolves toward: D# – A# – Cm – G#. Play each chord for one bar at a slow tempo, and listen to how A#maj9 sounds in that sequence — whether it feels like home, like a lift, or like a chord on its way somewhere else. Then play the same four chords in a different order, starting on A#maj9 itself, and notice how its character changes when it opens the progression instead of sitting inside it. On the piano, play the keys A#, D, F, A, C slowly and listen for each note of A#maj9 in turn.
For a second exercise, play A#maj9 and then the chord a fourth above A#, back and forth, four times each. That move — a chord and the chord a fourth above it — is the most common resolution in Western music, and it is the move A#maj9 is built for when it acts as a dominant. Finish by playing A#maj9 on its own, slowly, and naming each note out loud as you play it: A#, D, F, A, C. Naming the notes while you play them is what turns a shape into knowledge you can use in any key. Test yourself with the Practice Chord Quiz and keep time with the Metronome as the tempo rises. On the piano, A#maj9 is the keys A#, D, F, A, C, and the inversions above move the same notes around.
Frequently asked questions
Which fingers do you use for A#maj9 on piano?
In the right hand, start with the thumb on A# and one finger per note in order, ending with the little finger on C. In the left hand, mirror it with the little finger on the low A#. Longer fingers take the black keys, so check which notes of A#maj9 are black keys before you settle on a fingering.
What notes are in A#maj9?
A#maj9 contains A#, D, F, A, C: root A#, major 3rd D, perfect 5th F, major 7th A and the 9th C. It is a major 7th chord with the 9th added on top. On the piano, check the root-position keys above for that note.
Is A#maj9 a major chord?
Yes — a major 9th chord, built on a major triad with a major 7th and a 9th. It sounds major, lush and dreamy, and it works as a tonic chord. On the piano, check the root-position keys above for that note.
What is the difference between A#maj9 and A#maj7?
A#maj9 adds the 9th C to the major 7th chord. That extra note widens the sound and makes the chord feel more open and spacious. On the piano, check the root-position keys above for that note.
How do you play A#maj9 on the piano?
In root position, play the keys A#, D, F, A, C, with A# as the lowest note. That is the basic shape of A#maj9 on the piano. The inversions above put a different note in the bass, and the Chord Inverter shows every inversion of A#maj9 on the keyboard.