Scientific pitch notation

Scientific Pitch Notation in music is a method of naming the notes of the standard western chromatic scale by appending a number identifying each octave, so that each note is unambiguously defined according to its fundamental frequency.

Example: A4 is the A above middle C, and has a fundamental frequency of 440.00 Hz.

This notation is useful, for example, when describing the written pitch and sounding pitch of a transposing instrument.

See also