A3 — 220.00 Hz
A3 (MIDI 57) vibrates 220.00 times per second at standard concert pitch. Play the reference tone below, or tune to it with the online tuner.
A3 at different reference pitches
| Reference (A4) | A3 frequency | Used for |
|---|---|---|
| 415 Hz | 207.50 Hz | Baroque pitch |
| 432 Hz | 216.00 Hz | “Verdi” pitch |
| 440 Hz | 220.00 Hz | Standard concert pitch |
| 442 Hz | 221.00 Hz | European orchestras |
| 444 Hz | 222.00 Hz | European orchestras |
Physical properties
- Period: one cycle every 4.55 ms
- Wavelength in air: ≈ 1.56 m (at 20 °C, 343 m/s)
- MIDI note number: 57
- Octave up: A4 = 440.00 Hz · Octave down: 110.00 Hz