G♯1 / A♭1
Reviewed for accuracy · Maintained by Justin Evans
G♯1 highlighted — use the view toggle to see all 88 keys.
Piano key
12 of 88
Octave
1
Frequency
51.91 Hz
MIDI number
32
Key color
Black key
Pitch class
G# · Ab
What is G♯1?
G♯1 is the G♯ in octave 1 — the 12th key of the 88 on a full-size piano, counted from the bottom. In standard tuning it sounds at 51.91 Hz. It sits 28 half-steps below middle C (C4).
To find it, locate any group of two black keys: the white key just to their left is a C. Count down from middle C (C4) 3 octaves to reach octave 1, then step to G♯.
Every octave doubles the frequency: the G♯ one octave up sounds at 103.82 Hz and the one below at 25.96 Hz. The same piano key can be written as G#, Ab depending on the musical context — same sound, different spelling.
Nearby notes
Every G♯ on the keyboard: