# B♭ Suspended 2nd piano chord (B♭sus2)

B♭sus2 contains B♭, C and F. The third replaced by the second. B♭ is a black key; C and F are white.

- Canonical page: https://piano.org/chords/suspended-2nd/b-flat/
- Entity: chord:sus2:b-flat
- Notes: B♭ C F
- Formula: 1 2 5
- Intervals from root: P1, M2, P5
- Interval stack (semitones): 2 5
- Also written: B♭sus2, Bbsus2, B♭ suspended 2nd
- Parameters: A440, 12-TET, 165 mm octave, spans centre to centre

## Construction

| Degree | Note | Interval from root | Semitones |
| --- | --- | --- | --- |
| 1 | B♭ | Perfect unison | 0 |
| 2 | C | Major second | 2 |
| 5 | F | Perfect fifth | 7 |

## Fingering

Rest your right hand over the notes with finger 1 on B♭, finger 3 on C, finger 5 on F. The left hand mirrors it.
Right hand 1-3-5, left hand 5-3-1. Source: piano.org fingering method v1.

## Inversions

| Position | Bass | Notes in order | Figured bass | Span |
| --- | --- | --- | --- | --- |
| Root position | B♭ | B♭3 C4 F4 | 5/3 | 7 st, 96 mm |
| First inversion (B♭sus2/C) | C | C4 F4 B♭4 | 6/3 | 10 st, 138 mm |
| Second inversion (B♭sus2/F) | F | F4 B♭4 C5 | 6/4 | 7 st, 96 mm |

## Voicings (5)

| Voicing | Notes | Span | Relation | Omits or adds |
| --- | --- | --- | --- | --- |
| Close, root position | B♭3 C4 F4 | 7 st, 96 mm | identical | none |
| Close, first inversion | C4 F4 B♭4 | 10 st, 138 mm | identical | none |
| Close, second inversion | F4 B♭4 C5 | 7 st, 96 mm | identical | none |
| Open, fifth on top | B♭2 F3 C4 | 14 st, 193 mm | identical | none |
| Root and third only | B♭3 C4 | 2 st, 28 mm | subset | omits F |

## One-edit neighbors

| Becomes | Edit | Changes | Common tones |
| --- | --- | --- | --- |
| B♭add9 | 1 3 5 9 | adds D | 3 |
| B♭ | 1 3 5 | C becomes D | 2 |
| B♭m | 1 ♭3 5 | C becomes D♭ | 2 |
| B♭sus4 | 1 4 5 | C becomes E♭ | 2 |
| B♭maj7 | 1 3 5 7 | C becomes D, A | 2 |
| B♭7 | 1 3 5 ♭7 | C becomes D, A♭ | 2 |
| B♭m7 | 1 ♭3 5 ♭7 | C becomes D♭, A♭ | 2 |
| B♭mMaj7 | 1 ♭3 5 7 | C becomes D♭, A | 2 |
| B♭7sus4 | 1 4 5 ♭7 | C becomes E♭, A♭ | 2 |
| B♭6 | 1 3 5 6 | C becomes D, G | 2 |
| B♭m6 | 1 ♭3 5 6 | C becomes D♭, G | 2 |
| B♭dim | 1 ♭3 ♭5 | C, F becomes D♭, F♭ | 1 |

## Set theory

- Absolute pitch classes: {10, 0, 5}
- Relative pitch classes: [0, 2, 7]
- Normal order: [10, 0, 5]
- Prime form: (027)
- Forte number: 3-9
- Interval vector: <010020>

## Frequencies (close root position)

| Note | MIDI | Frequency |
| --- | --- | --- |
| B♭3 | 58 | 233.08 Hz |
| C4 | 60 | 261.63 Hz |
| F4 | 65 | 349.23 Hz |

## Questions and answers

### What notes are in B♭sus2?

B♭sus2 contains B♭, C and F. The formula is 1, 2, 5.

### How do you play B♭sus2 on piano?

Play B♭, C and F together. Right hand fingers 1, 3, 5; left hand 5, 3, 1. B♭ is a black key; C and F are white.

### What are the inversions of B♭sus2?

3 positions: root position B♭ C F, B♭sus2/C, B♭sus2/F.

### What is the difference between B♭sus2 and B♭add9?

Adds D. 3 of the notes are shared.

### What is an easy B♭sus2 for small hands?

The root and third only voicing, B♭3 C4, spans 2 semitones or about 28 mm.

### What are the frequencies of B♭sus2?

From B♭3 at A440 in 12-TET: 233.08, 261.63, 349.23 Hz.

### What is the set class of B♭sus2?

Prime form (027), Forte 3-9, interval vector &lt;010020&gt;.

### How do I transpose B♭sus2 to another key?

Keep the 1, 2, 5 formula on the new root. Csus2 is C, D, G; C♯sus2 is C♯, D♯, G♯.

### Is A♯sus2 the same as B♭sus2?

Enharmonically yes: the same piano keys and the same sound, spelled differently.

## Provenance

Every derived value above is computed by the piano.org theory kernel from the root, the quality and the stated parameters. Nothing is hand-entered per chord.

Machine record: https://piano.org/api/knowledge/v1/entities/chord:sus2:b-flat
Last reviewed: 2026-08-12