Note	Frequency (Hz)
C	261.63
C#	277.18
D	293.67
D#	311.13
E	329.63
F	349.23
F#	369.99
G	392.00
G#	415.31
A	440.00
A#	466.16
B	493.88
Cn	523.25

Notes: ♯ indicates flat; ♭ indicates sharp; n indicates return to natural; Hz is Hertz.

The lowest frequency distinguishable as a note is about 20 hertz. The highest audible frequency is about 20,000 hertz. A hertz (Hz) is a unit of frequency that measures the number of the wave cycles per second frequency of a periodic phenomenon whose periodic time is one second (cycles per second).