A5
A5 highlighted — use the view toggle to see all 88 keys.
Piano key
61 of 88
Octave
5
Frequency
880 Hz
MIDI number
81
Key color
White key
Pitch class
A, G##, Bbb
What is A5?
A5 is the A in octave 5 — the 61st key of the 88 on a full-size piano, counted from the bottom. In standard tuning it sounds at 880 Hz. It sits 21 half-steps above middle C (C4).
To find it, locate any group of two black keys: the white key just to their left is a C. Count up from middle C (C4) 1 octave to reach octave 5, then step to A.
Every octave doubles the frequency: the A one octave up sounds at 1760 Hz and the one below at 440 Hz. The same piano key can be written as A, G##, Bbb depending on the musical context — same sound, different spelling.
Nearby notes
Every A on the keyboard: