Convert note and octave to Hz or frequency to musical note, with cents, period and adjustable A4 reference. Convert quickly between note names and frequencies for tuning, acoustics and music study. Choose a note and octave to calculate Hz from the A4 reference. In reverse mode, enter Hz to get the nearest note, octave, and cents deviation. The tool is designed to give a quick answer without hiding the musical logic. Explore the controls, listen whenever playback is available, and compare alternatives before choosing what fits your song. It is useful for tuning, synthesis, acoustics, audio testing, exercise design, and understanding equal temperament mathematically. It also supports harmony study, songwriting, rehearsal, and setlist preparation. Results can be copied and combined with the other tools in the Musician Toolkit. Try the same example in different keys. Comparing scale degrees, intervals, and notes helps you recognize patterns that appear in many songs. 440 Hz is a widely used international concert-pitch reference, though other references are possible. There are 100 cents in an equal-tempered semitone. Cents show how far a frequency is from the nearest tempered pitch. Yes. Calculations use 12-tone equal temperament.Note Frequency Calculator
Note → frequency
Frequency → note
About this tool
How to use
How to use the frequency calculator
When this tool is most useful
Study tip
Frequently asked questions
Why is A4 usually 440 Hz?
What are cents?
Does it use equal temperament?
Music practice
Note Frequency Calculator
Calculate any note frequency in Hz or identify the nearest note from a frequency. Adjustable A4, cents and period.
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