G♯4 / A♭4
415.305Hz at concert pitch
Press to hear a pure sine tone at this pitch.
MIDI note
68
Piano key
48
Octave
4
Frequency
415.305 Hz
Period
2.4079 ms
Wavelength
0.8259 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 G♯s share one. Enharmonic spellings (G♯4 and A♭4) name the same pitch two ways.
At other reference pitches
| Reference (A4) | G♯4 frequency | Where you meet it |
|---|---|---|
| 432 Hz | 407.754 Hz | the alternative-tuning circle |
| 440 Hzstandard | 415.305 Hz | the ISO 16 standard — concert pitch |
| 442 Hz | 417.192 Hz | many European orchestras tune a touch sharp |
| 443 Hz | 418.136 Hz | some sharper continental orchestras |
Every row is G♯4 — only the A4 you tune to changes. A frequency scales straight with the reference: G♯4 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.