A♭4 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 | A♭4 | vs 440 |
|---|---|---|
| A4 = 415 Hz · Baroque pitch | 391.71 Hz | −101.3¢ |
| A4 = 432 Hz · “Verdi” pitch | 407.75 Hz | −31.8¢ |
| A4 = 440 Hz · Standard (ISO 16) | 415.30 Hz | — |
| A4 = 442 Hz · Orchestral | 417.19 Hz | +7.9¢ |
One cycle of A♭4 lasts 2.408 ms, and its wavelength in air at 20 °C is 82.6 cm. Hold it as a steady tone in the tone generator.
A♭4 on the piano
A♭4 is key 48 of 88, counting from the bottom — the black key between G and A. Press any key below to compare it with its neighbours.
A♭4 on the guitar
In standard tuning A♭4 is played in 4 places: 4th (D) string, fret 18, 3rd (G) string, fret 13, 2nd (B) string, fret 9 and 1st (high E) string, fret 4. 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 A♭5.
A♭4 on the staff
Instruments that can play A♭4
45 instruments play A♭4 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
Tuned percussion
Only at the extreme of their range
Voices: A♭4 is inside the typical range of the baritone, tenor, alto, mezzo-soprano and soprano. Test your own range.
The harmonics of A♭4
A played A♭4 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) | 415.30 Hz | A♭4 | 0¢ |
| 2 | 830.61 Hz | A♭5 | 0¢ |
| 3 | 1245.9 Hz | E♭6 | +2.0¢ |
| 4 | 1661.2 Hz | A♭6 | 0¢ |
| 5 | 2076.5 Hz | C7 | −13.7¢ |
| 6 | 2491.8 Hz | E♭7 | +2.0¢ |
| 7 | 2907.1 Hz | F♯7 | −31.2¢ |
| 8 | 3322.4 Hz | A♭7 | 0¢ |
Frequencies that land on A♭4
Frequently asked questions
What is the frequency of A♭4?
A♭4 is 415.30 Hz in equal temperament with A4 tuned to 440 Hz, the international standard. At A4 = 432 Hz it is 407.75 Hz, and at the orchestral A4 = 442 Hz it is 417.19 Hz.
Is A♭4 the same note as G♯4?
On a piano, a guitar or a tuner, yes: A♭4 and G♯4 are the same key and the same frequency, 415.30 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 A♭4 on a piano?
A♭4 is key 48 of 88, counting from the bottom — the black key between G and A.
Which instruments can play A♭4?
45 of the instruments we chart play A♭4 within their normal range, including violin, viola, cello, erhu, guitar, and 3 more reach it only at the extreme of their range.
Typing it? A♭4 is also written Ab4 or G#4. Convert any frequency on the Hz-to-note converter.