B♭ Major 7th Chord (Bbmaj7, A#maj7) on Piano
The Bbmaj7 chord (Bb major 7th) is built from 4 notes: Bb – D – F – A. It is also written as A#maj7.
Play these notes on a MIDI keyboard, your computer keyboard, or the on-screen keys and ChordKeys will name the chord back to you.
Notes and intervals
| Note | Degree | Interval from Bb | Semitones |
|---|---|---|---|
| Bb | 1 | root | 0 |
| D | 3 | major 3rd | 4 |
| F | 5 | perfect 5th | 7 |
| A | 7 | major 7th | 11 |
Inversions
Rearranging which note sits at the bottom gives you 4 playable voicings of the same chord. Inversions let you move between chords with less hand movement.
| Voicing | Notes | Bass note |
|---|---|---|
| Root position | Bb – D – F – A | Bb in the bass |
| 1st inversion | D – F – A – Bb | D in the bass |
| 2nd inversion | F – A – Bb – D | F in the bass |
| 3rd inversion | A – Bb – D – F | A in the bass |
How the major 7th chord is built
Every major 7th chord uses the same interval formula: 1 (0 semitones), 3 (4 semitones), 5 (7 semitones), 7 (11 semitones). Starting on Bb and applying that formula produces Bb, D, F, A. Learn the formula once and you can build a major 7th chord on any of the twelve roots.
Keys that contain Bbmaj7
Every note of Bbmaj7 belongs to these keys, so it will sit naturally in a progression written in any of them.
Other chords on Bb
Major 7th chords on other roots
Frequently asked questions
What notes are in a Bbmaj7 chord?
A Bbmaj7 chord contains the notes Bb, D, F, A. Those are the 1, 3, 5, 7 degrees measured from the root note Bb.
How do you play Bbmaj7 on piano?
Place your thumb on Bb, then add D and F and A above it. With a right hand in root position the common fingering is 1–2–3–5.
Is Bbmaj7 the same as A#maj7?
Yes. Bbmaj7 and A#maj7 are enharmonic equivalents — they sound identical and use the same piano keys. Which spelling you use depends on the key you are playing in.