Note frequency

Any note name and octave → Hz on the equal-tempered scale, with adjustable A4.

Calculated in this browser. Nothing is sent anywhere.

Equal temperament (12-TET) with adjustable A4 reference (415–466 Hz, default 440). Just intonation and historical temperaments differ. Octaves −1–9.

How to use

  1. Pick the note and octave.
  2. Set A4 if it is not 440 Hz.
  3. Read the frequency and MIDI number.

What it supports

Equal temperament only, octaves −1 to 9, A4 between 415–466 Hz. Just intonation and historical temperaments differ.

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