G1
48.999Hz at concert pitch
Press to hear a pure sine tone at this pitch.
MIDI note
31
Piano key
11
Octave
1
Frequency
48.999 Hz
Period
20.4086 ms
Wavelength
7.0001 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.
At other reference pitches
| Reference (A4) | G1 frequency | Where you meet it |
|---|---|---|
| 432 Hz | 48.109 Hz | the alternative-tuning circle |
| 440 Hzstandard | 48.999 Hz | the ISO 16 standard — concert pitch |
| 442 Hz | 49.222 Hz | many European orchestras tune a touch sharp |
| 443 Hz | 49.334 Hz | some sharper continental orchestras |
Every row is G1 — only the A4 you tune to changes. A frequency scales straight with the reference: G1 at 432 Hz is the 440 Hz value times 432⁄440.
Move around
Every G
Chords with G in them
G appears in each of these — see the whole chord grid.