D0
18.354Hz at concert pitch
Press to hear a pure sine tone at this pitch.
MIDI note
14
Piano key
—
Octave
0
Frequency
18.354 Hz
Period
54.484 ms
Wavelength
18.688 m
Pitch class
D
Notation
SPN
MIDI is the note number synths and software pass around (0–127). Pitch class is the note without its octave — all the Ds share one. This note falls outside the 88-key piano, so it has no piano key number.
At other reference pitches
| Reference (A4) | D0 frequency | Where you meet it |
|---|---|---|
| 432 Hz | 18.02 Hz | the alternative-tuning circle |
| 440 Hzstandard | 18.354 Hz | the ISO 16 standard — concert pitch |
| 442 Hz | 18.437 Hz | many European orchestras tune a touch sharp |
| 443 Hz | 18.479 Hz | some sharper continental orchestras |
Every row is D0 — only the A4 you tune to changes. A frequency scales straight with the reference: D0 at 432 Hz is the 440 Hz value times 432⁄440.
Move around
Every D
Chords with D in them
D appears in each of these — see the whole chord grid.