D9

9,397.273Hz at concert pitch

Press to hear a pure sine tone at this pitch.
MIDI note
122
Piano key
Octave
9
Frequency
9,397.273 Hz
Period
0.1064 ms
Wavelength
0.0365 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)D9 frequencyWhere you meet it
432 Hz9,226.413 Hzthe alternative-tuning circle
440 Hzstandard9,397.273 Hzthe ISO 16 standard — concert pitch
442 Hz9,439.987 Hzmany European orchestras tune a touch sharp
443 Hz9,461.345 Hzsome sharper continental orchestras

Every row is D9 — only the A4 you tune to changes. A frequency scales straight with the reference: D9 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.