B2
123.471Hz at concert pitch
Press to hear a pure sine tone at this pitch.
MIDI note
47
Piano key
27
Octave
2
Frequency
123.471 Hz
Period
8.0991 ms
Wavelength
2.778 m
Pitch class
B
Notation
SPN
MIDI is the note number synths and software pass around (0–127). Pitch class is the note without its octave — all the Bs share one.
At other reference pitches
| Reference (A4) | B2 frequency | Where you meet it |
|---|---|---|
| 432 Hz | 121.226 Hz | the alternative-tuning circle |
| 440 Hzstandard | 123.471 Hz | the ISO 16 standard — concert pitch |
| 442 Hz | 124.032 Hz | many European orchestras tune a touch sharp |
| 443 Hz | 124.313 Hz | some sharper continental orchestras |
Every row is B2 — only the A4 you tune to changes. A frequency scales straight with the reference: B2 at 432 Hz is the 440 Hz value times 432⁄440.
Move around
Every B
Chords with B in them
B appears in each of these — see the whole chord grid.