AbraCalc

1 Semitone Frequency Ratio

One semitone corresponds to a frequency ratio of approximately 1.0595 (the twelfth root of 2).

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  1. Enter semitones in the fields above.
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  3. Read your frequency ratio and the full breakdown beneath it.

One semitone is the smallest interval in Western music, with a frequency ratio of the twelfth root of 2, roughly 1.0595.

Frequently asked questions

What is the frequency ratio of an octave?
An octave is exactly 12 semitones, corresponding to a frequency ratio of 2:1.
What is the perfect fifth ratio?
A perfect fifth is 7 semitones; the equal-temperament ratio is 2^(7/12) ≈ 1.4983.