B♭3 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♭3 | vs 440 |
|---|---|---|
| A4 = 415 Hz · Baroque pitch | 219.84 Hz | −101.3¢ |
| A4 = 432 Hz · “Verdi” pitch | 228.84 Hz | −31.8¢ |
| A4 = 440 Hz · Standard (ISO 16) | 233.08 Hz | — |
| A4 = 442 Hz · Orchestral | 234.14 Hz | +7.9¢ |
One cycle of B♭3 lasts 4.290 ms, and its wavelength in air at 20 °C is 1.47 m. Hold it as a steady tone in the tone generator.
B♭3 on the piano
B♭3 is key 38 of 88, counting from the bottom — the black key between A and B. Press any key below to compare it with its neighbours.
B♭3 on the guitar
In standard tuning B♭3 is played in 4 places: 6th (low E) string, fret 18, 5th (A) string, fret 13, 4th (D) string, fret 8 and 3rd (G) string, fret 3. The same pitch in each place, with a different tone: lower strings sound warmer. Guitar music is written an octave higher than it sounds, so on a guitar part this note is printed as B♭4.
B♭3 on the staff
Instruments that can play B♭3
42 instruments play B♭3 within the normal range, and 3 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.
Guitars and basses
Plucked and struck strings
Woodwind
Brass
Only at the extreme of their range
Voices: B♭3 is inside the typical range of the bass, baritone, tenor, alto and mezzo-soprano. Test your own range.
The harmonics of B♭3
A played B♭3 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) | 233.08 Hz | B♭3 | 0¢ |
| 2 | 466.16 Hz | B♭4 | 0¢ |
| 3 | 699.25 Hz | F5 | +2.0¢ |
| 4 | 932.33 Hz | B♭5 | 0¢ |
| 5 | 1165.4 Hz | D6 | −13.7¢ |
| 6 | 1398.5 Hz | F6 | +2.0¢ |
| 7 | 1631.6 Hz | A♭6 | −31.2¢ |
| 8 | 1864.7 Hz | B♭6 | 0¢ |
Frequently asked questions
What is the frequency of B♭3?
B♭3 is 233.08 Hz in equal temperament with A4 tuned to 440 Hz, the international standard. At A4 = 432 Hz it is 228.84 Hz, and at the orchestral A4 = 442 Hz it is 234.14 Hz.
Is B♭3 the same note as A♯3?
On a piano, a guitar or a tuner, yes: B♭3 and A♯3 are the same key and the same frequency, 233.08 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♭3 on a piano?
B♭3 is key 38 of 88, counting from the bottom — the black key between A and B.
Which instruments can play B♭3?
42 of the instruments we chart play B♭3 within their normal range, including violin, viola, cello, guitar, 7-string guitar, and 3 more reach it only at the extreme of their range.
Typing it? B♭3 is also written Bb3 or A#3. Convert any frequency on the Hz-to-note converter.