Note frequencies for equal-tempered scale

Usage no npm install needed!

<script type="module">
  import audioNotes from '';


Audio Notes

Provides note frequencies for equal-tempered scale.

Available on NPM.

CommonJS-ready or standalone window.AudioNotes.


With NodeJS or browserify:

var AudioNotes = require("audio-notes");

With standalone script embedding:

var AudioNotes = window.AudioNotes;


You can access notes with two conventions:

by note name

You can access the note frequency with its name (English notation).

Major notes use a upper-case where minor (sharp) notes use the lower-case convention. Then we add the octave number.


AudioNotes.A4 is a A (la in solfège) of the 4th octave (A4 is 440 Hz).

AudioNotes.a4 is a A# (la# in solfège) of the 4th octave (A4 is ~ 466.16 Hz).

The 12 notes of one octaves are: C c D d E F f G g A a B.

by MIDI value

You can also access a note by index:

AudioNotes[57] is the 57th notes of a midi keyboard, it is A4 .