B♭ Major Chord (Bb, A#) on Piano
The Bb chord (Bb major) is built from 3 notes: Bb – D – F. It is also written as A#.
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 |
Inversions
Rearranging which note sits at the bottom gives you 3 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 | Bb in the bass |
| 1st inversion | D – F – Bb | D in the bass |
| 2nd inversion | F – Bb – D | F in the bass |
How the major chord is built
Every major chord uses the same interval formula: 1 (0 semitones), 3 (4 semitones), 5 (7 semitones). Starting on Bb and applying that formula produces Bb, D, F. Learn the formula once and you can build a major chord on any of the twelve roots.
Keys that contain Bb
Every note of Bb belongs to these keys, so it will sit naturally in a progression written in any of them.
Other chords on Bb
Major chords on other roots
Frequently asked questions
What notes are in a Bb chord?
A Bb chord contains the notes Bb, D, F. Those are the 1, 3, 5 degrees measured from the root note Bb.
How do you play Bb on piano?
Place your thumb on Bb, then add D and F above it. With a right hand in root position the common fingering is 1–3–5.
Is Bb the same as A#?
Yes. Bb and A# are enharmonic equivalents — they sound identical and use the same piano keys. Which spelling you use depends on the key you are playing in.