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Note to Frequency Calculator

Calculate the exact frequency in Hz for any musical note. Select a note and octave to find its frequency. Supports different tuning standards.

C4

261.63 Hz

MIDI Note:
60
Wavelength:
1.31 m
Period:
3.82 ms
Octave Below:
130.81 Hz

Same Note Across All Octaves

Note Frequency (Hz) MIDI Description

The Formula

Frequency Calculation:
f = 440 × 2^((n-69)/12)

Where f is the frequency in Hz and n is the MIDI note number (A4 = 69).

Alternative Formula:
f = 440 × 2^((semitones from A4)/12)

Calculate semitones from A4, then apply the power of 2 relationship.

Key Relationships

  • Octave: Doubling the frequency raises pitch by one octave
  • Semitone: Multiply by 2^(1/12) ≈ 1.0595 for one semitone up
  • Fifth: Multiply by 2^(7/12) ≈ 1.498 for a perfect fifth

Frequently Asked Questions

440 Hz is the international standard tuning for A4. Some musicians prefer 432 Hz, claiming it sounds warmer or more natural. The difference is about 32 cents (less than a quarter tone). Most modern music uses 440 Hz, but you can use our calculator to find frequencies for any reference pitch.

MIDI note numbers are a standard way to represent musical notes as integers from 0 to 127. Middle C (C4) is MIDI note 60, and A4 (440 Hz) is MIDI note 69. Each number represents one semitone, making it easy for electronic instruments and software to communicate.

Some orchestras, particularly in Europe, tune to 442 Hz or even higher (443-444 Hz) for a brighter sound that projects better in large concert halls. This is a preference that varies by orchestra, conductor, and repertoire being performed.
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