B5
Reviewed for accuracy · Maintained by Justin Evans
B5 highlighted — use the view toggle to see all 88 keys.
Piano key
63 of 88
Octave
5
Frequency
987.77 Hz
MIDI number
83
Key color
White key
Pitch class
B · Cb · A##
What is B5?
B5 is the B in octave 5 — the 63rd key of the 88 on a full-size piano, counted from the bottom. In standard tuning it sounds at 987.77 Hz. It sits 23 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 B.
Every octave doubles the frequency: the B one octave up sounds at 1975.54 Hz and the one below at 493.89 Hz. The same piano key can be written as B, Cb, A## depending on the musical context — same sound, different spelling.
Nearby notes
Every B on the keyboard: