D#4 — 311.13 Hz
D#4 (MIDI 63) vibrates 311.13 times per second at standard concert pitch. Play the reference tone below, or tune to it with the online tuner.
D#4 at different reference pitches
| Reference (A4) | D#4 frequency | Used for |
|---|---|---|
| 415 Hz | 293.45 Hz | Baroque pitch |
| 432 Hz | 305.47 Hz | “Verdi” pitch |
| 440 Hz | 311.13 Hz | Standard concert pitch |
| 442 Hz | 312.54 Hz | European orchestras |
| 444 Hz | 313.96 Hz | European orchestras |
Physical properties
- Period: one cycle every 3.21 ms
- Wavelength in air: ≈ 1.10 m (at 20 °C, 343 m/s)
- MIDI note number: 63
- Octave up: D#5 = 622.25 Hz · Octave down: 155.56 Hz