Note Frequency Chart
Enter scientific pitch notation such as A4 or C4, choose the A4 reference, and calculate frequency.
A QUICK WALKTHROUGH
How to use this tool
- Enter a note name A–G with optional sharp or flat and an octave.
- Choose a reference A4 frequency such as 440 Hz.
- Read the equal-temperament frequency and cents comparison.
Equal temperament
The calculation uses f = A4 × 2^(n/12), where n is semitones from A4. Octaves double frequency and a semitone is 100 cents.
Reference pitch
A4 is user-selectable. Cents compare the chosen reference with A440 using 1200 × log₂(reference / 440). This is a tuning comparison, not an audio measurement.
GOOD TO KNOW
Common questions
Which notes are supported?
Scientific pitch notation from C0 through B8: C, D, E, F, G, A, B and C#/Db, D#/Eb, F#/Gb, G#/Ab, A#/Bb. Other spellings such as Cb or E# are not supported.
What is a cent?
A cent is one hundredth of an equal-tempered semitone; an octave is 1200 cents.
Does it generate sound?
No. It only calculates frequencies locally in the browser.