D3

146.832Hz at concert pitch

Press to hear a pure sine tone at this pitch.
MIDI note
50
Piano key
30
Octave
3
Frequency
146.832 Hz
Period
6.8105 ms
Wavelength
2.336 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.

At other reference pitches

Reference (A4)D3 frequencyWhere you meet it
432 Hz144.163 Hzthe alternative-tuning circle
440 Hzstandard146.832 Hzthe ISO 16 standard — concert pitch
442 Hz147.5 Hzmany European orchestras tune a touch sharp
443 Hz147.834 Hzsome sharper continental orchestras

Every row is D3 — only the A4 you tune to changes. A frequency scales straight with the reference: D3 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.