Note Frequency Reference
Frequency in Hz for every note and octave, in standard equal temperament.
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| Note | Frequency (Hz) |
|---|
About this reference
Standard 12-tone equal temperament splits every octave into 12 equal ratios, so each semitone's frequency is the one before it times 2^(1/12) — that's why frequency exactly doubles one octave up (A5 is exactly 2× A4) but doesn't increase by an equal number of Hz per semitone. A4 = 440 Hz is the modern concert-pitch standard, but some orchestras and eras tune slightly sharp or flat (442 Hz is common in parts of Europe) — adjust the reference pitch above to see every other note shift with it.
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