Root position
A# – D# – E#The root A# is the lowest note. This is the shape most people learn first.
3 notes · 1 · 4 · 5
A# Suspended Fourth Piano Chord (A#sus4)
A#sus4 is built from A#, D# and E# — the formula 1 · 4 · 5, or 5 and 7 semitones above A#. The shape uses 1 white and 2 black keys, and you can hear it, invert it and compare it below.
Chord
A# Suspended fourth
Notes
A# · D# · FFormula
1 · 4 · 5Right hand
1 · 4 · 5C
D
E
F
G
A
B
C
C#
D#
F#
G#
A#
Choose a chord, then play it. Finger numbers run from thumb (1) to little finger (5).
The finder above already holds A#sus4. Press P or the Play chord button to hear A#, D#, E# sounded together, then change the root or the chord type to compare it with something else.
Chord tones
The notes in A#sus4
A suspended fourth chord replaces the third with the fourth degree. The fourth sits one semitone above the major third and leans onto it, so a sus4 is usually heard as a delay that resolves into the plain triad underneath it.
| Note | Interval | Degree | Semitones | Right hand |
|---|---|---|---|---|
| A#black key | Root | 1 | 0 | 1 · thumb |
| D#black key | Perfect fourth | 4 | 5 | 4 · ring finger |
| E#white key | Perfect fifth | 5 | 7 | 5 · little finger |
Step by step
How to play A#sus4 on piano
- Find A#: it is the third black key in a group of three.
- Build upwards from A# using 5 and 7 semitones to reach D# and E#.
- With the right hand, place finger 1 on A#, finger 4 on D# and finger 5 on E#. Keep the wrist level and the knuckles rounded.
- Move your hand a little further in towards the fallboard so the black keys sit comfortably under your fingers.
- Play the notes together, then one at a time from the bottom up, and listen to how A#sus4 settles.
- Try first inversion as well: D# – E# – A#. Inversions let you change chords without jumping around the keyboard.
Inversions
A#sus4 in 3 positions
An inversion keeps the same 3 notes and simply moves the lowest one up an octave. Learning them means you can change chords with small hand movements instead of jumping to a new part of the keyboard.
First inversion
D# – E# – A#D# is the lowest note, so the perfect fourth sits in the bass and the notes below it move up an octave.
Second inversion
E# – A# – D#E# is the lowest note, so the perfect fifth sits in the bass and the notes below it move up an octave.
In context
Which keys contain A#sus4
In D♭ major the chord functions as visus4. Altogether it is produced by the scales of 10 keys, so learning it once pays off in several places.
- D♭ majorvisus4
- E♭ majorVsus4
- F♯ majoriiisus4
- A♭ majoriisus4
- B♭ majorIsus4
- C minorVIIsus4
- E♭ minorvsus4
- F minorivsus4
- G minorIIIsus4
- B♭ minorisus4
Chord tones are spelled by the degree they occupy, so the third of a minor chord is written as a flat rather than a sharp even though it is the same key on the piano. A double sharp such as F## means the key one whole tone above F.
Compare
A#sus4 against A# major
A#sus4 and A# major share A# and E#. Moving the major third C## up 1 semitone to the perfect fourth D# turns A# major into A#sus4.
Practise the pair together: hold the shared notes A#, E# still and move only the one finger. Hearing that single change is the quickest way to recognise the two chords by ear.
Open A# major →Good questions
A#sus4 questions
What notes are in the A#sus4 chord?
A#sus4 contains A#, D# and E#. Counted from the root, that is the formula 1 · 4 · 5, or 5 and 7 semitones above A#.
What is the right-hand fingering for A#sus4?
A comfortable beginner fingering is 1 (thumb) on A#, 4 (ring finger) on D# and 5 (little finger) on E#. Finger numbers run from the thumb (1) to the little finger (5), and they change once you start using inversions.
How is A#sus4 different from A# major?
A#sus4 and A# major share A# and E#. Moving the major third C## up 1 semitone to the perfect fourth D# turns A# major into A#sus4.
Which keys use the A#sus4 chord?
It occurs naturally in D♭ major (visus4), E♭ major (Vsus4), F♯ major (iiisus4), A♭ major (iisus4), B♭ major (Isus4) and C minor (VIIsus4) among others. The roman numeral shows which degree of the key the chord is built on.
What are the inversions of A#sus4?
root position is A# – D# – E#, first inversion is D# – E# – A# and second inversion is E# – A# – D#. Every inversion holds the same notes; only the lowest one changes.
Is A#sus4 the same as the B♭ chord?
On an equal-tempered piano A# and B♭ are the same key, so the chords sound identical. Written music chooses between them according to the key signature: pages here are named after the sharp spelling of the root, and the chord tones are then spelled by the degree each one occupies, which is why a double sharp occasionally appears.