Hz to Note Converter
This free Hz to Note Converter converts both ways: from frequency (Hz) to note name and from note name to Hz.
Use it for tuning, sound design, and quick pitch checks while producing.
Formula used: note = 69 + 12 * log2(f/A4), and frequency = A4 * 2^((midi-69)/12).
What is a Hz to note converter?
A Hz to note converter takes a frequency value in hertz and tells you the closest musical note, the exact frequency of that note, and how far off you are in cents. It works in both directions, so you can also enter a note name and octave to get the exact Hz value. Useful for tuning synths, identifying resonant frequencies, and pitch-checking samples.
What is the frequency of A4?
A4 is 440 Hz in standard tuning, which is the international reference pitch used to tune most instruments. Some producers and orchestras tune to 432 Hz or 441 Hz instead. This converter lets you set a custom A4 tuning reference so all note calculations reflect your actual tuning standard.
How do I convert Hz to a musical note?
The formula is: note = 69 + 12 x log2(f / A4). The result is a MIDI note number, which maps directly to a note name and octave. For example, 440 Hz gives MIDI note 69, which is A4. Anything between two notes returns the closest note plus a cents offset showing how sharp or flat the frequency is.
What is a cents offset?
Cents measure the distance between a frequency and the nearest exact note. There are 100 cents in a semitone. A cents offset of 0 means the frequency is perfectly in tune. Plus 50 cents means it's halfway between two notes sharp; minus 50 means halfway flat. This is the same scale used by hardware and software tuners.
What is a musical note frequency chart?
A musical note frequency chart lists every note across the piano range alongside its exact Hz value. A4 is 440 Hz, A3 is 220 Hz, A5 is 880 Hz, and so on, each octave doubles the frequency. This converter effectively gives you an interactive version of that chart, letting you look up any note or frequency instantly.