B♭0 at every common reference pitch
A note’s frequency depends on what A4 is tuned to. The standard is 440 Hz; the other three are the ones you are most likely to meet. The cents column is how far each one sits from the 440 version — the same for every note, because changing the reference moves the whole scale together.
| Reference | B♭0 | vs 440 |
|---|---|---|
| A4 = 415 Hz · Baroque pitch | 27.48 Hz | −101.3¢ |
| A4 = 432 Hz · “Verdi” pitch | 28.61 Hz | −31.8¢ |
| A4 = 440 Hz · Standard (ISO 16) | 29.14 Hz | — |
| A4 = 442 Hz · Orchestral | 29.27 Hz | +7.9¢ |
One cycle of B♭0 lasts 34.323 ms, and its wavelength in air at 20 °C is 11.77 m. Hold it as a steady tone in the tone generator.
B♭0 on the piano
B♭0 is key 2 of 88, counting from the bottom — the black key between A and B. Press any key below to compare it with its neighbours.
B♭0 on the guitar
B♭0 is below the guitar’s lowest note, the open low E (E2), so a guitar in standard tuning cannot play it.
B♭0 on the staff
Instruments that can play B♭0
2 instruments play B♭0 within the normal range, and 1 reach it only at the extreme of theirs. Each links to its range chart; for a transposing instrument, the note on its part is shown.
Woodwind
Keyboards and free reeds
Only at the extreme of their range
B♭0 is outside the typical range of all six voice types. Test your own range.
The harmonics of B♭0
A played B♭0 is not one frequency. A string or a pipe also sounds whole-number multiples of it, and the mix of those harmonics is the instrument’s tone. Here is where the first eight land — and why the 7th sounds out of tune against a piano.
| Harmonic | Frequency | Nearest note | Off by |
|---|---|---|---|
| 1 (fundamental) | 29.14 Hz | B♭0 | 0¢ |
| 2 | 58.27 Hz | B♭1 | 0¢ |
| 3 | 87.41 Hz | F2 | +2.0¢ |
| 4 | 116.54 Hz | B♭2 | 0¢ |
| 5 | 145.68 Hz | D3 | −13.7¢ |
| 6 | 174.81 Hz | F3 | +2.0¢ |
| 7 | 203.95 Hz | A♭3 | −31.2¢ |
| 8 | 233.08 Hz | B♭3 | 0¢ |
Frequently asked questions
What is the frequency of B♭0?
B♭0 is 29.14 Hz in equal temperament with A4 tuned to 440 Hz, the international standard. At A4 = 432 Hz it is 28.61 Hz, and at the orchestral A4 = 442 Hz it is 29.27 Hz.
Is B♭0 the same note as A♯0?
On a piano, a guitar or a tuner, yes: B♭0 and A♯0 are the same key and the same frequency, 29.14 Hz, in equal temperament. They are two names for one pitch (enharmonic equivalents). Which one is written depends on the key — sharps in sharp keys, flats in flat keys — and a string or wind player may pitch them a few cents apart when playing in just intonation.
How do I play B♭0 on a piano?
B♭0 is key 2 of 88, counting from the bottom — the black key between A and B.
Which instruments can play B♭0?
2 of the instruments we chart play B♭0 within their normal range, including contrabassoon, piano, and 1 more reach it only at the extreme of their range.
Typing it? B♭0 is also written Bb0 or A#0. Convert any frequency on the Hz-to-note converter.