G9

12,543.854Hz at concert pitch

Press to hear a pure sine tone at this pitch.
MIDI note
127
Piano key
Octave
9
Frequency
12,543.854 Hz
Period
0.0797 ms
Wavelength
0.0273 m
Pitch class
G
Notation
SPN

MIDI is the note number synths and software pass around (0–127). Pitch class is the note without its octave — all the Gs share one. This note falls outside the 88-key piano, so it has no piano key number.

At other reference pitches

Reference (A4)G9 frequencyWhere you meet it
432 Hz12,315.784 Hzthe alternative-tuning circle
440 Hzstandard12,543.854 Hzthe ISO 16 standard — concert pitch
442 Hz12,600.871 Hzmany European orchestras tune a touch sharp
443 Hz12,629.38 Hzsome sharper continental orchestras

Every row is G9 — only the A4 you tune to changes. A frequency scales straight with the reference: G9 at 432 Hz is the 440 Hz value times 432⁄440.

About this note

The top of the MIDI note range — number 127, the highest note the 7-bit MIDI standard can name. Its fundamental sits above the top of most adult hearing, so it's more a limit of the protocol than a note you'd play.

Move around

Semitone down
F♯9
Semitone up
Octave down
G8
Octave up

Every G

Chords with G in them

G appears in each of these — see the whole chord grid.