F1
F1 highlighted — use the view toggle to see all 88 keys.
Piano key
9 of 88
Octave
1
Frequency
43.65 Hz
MIDI number
29
Key color
White key
Pitch class
F, E#, Gbb
What is F1?
F1 is the F in octave 1 — the 9th key of the 88 on a full-size piano, counted from the bottom. In standard tuning it sounds at 43.65 Hz. It sits 31 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 F.
Every octave doubles the frequency: the F one octave up sounds at 87.3 Hz and the one below at 21.83 Hz. The same piano key can be written as F, E#, Gbb depending on the musical context — same sound, different spelling.
Nearby notes
Every F on the keyboard: