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Note Frequency Reference
Find the exact frequency of any musical note and play it.
Every note’s exact pitch
Each musical note has a precise frequency, set by equal temperament with A4 fixed at 440 Hz. This tool gives the exact hertz for any note and plays it so you can tune by ear.
Choose a note and octave and it shows the frequency — A4 is 440 Hz, middle C is about 261.63 Hz. Press play to hear a pure tone at that pitch.
Precise and private
The calculation and tone run in your browser, so nothing is uploaded.
Frequently Asked Questions
How are frequencies calculated?
From equal temperament with A4 at 440 Hz. Each semitone is a factor of the twelfth root of two.
What does it play?
A pure tone at the selected note’s frequency, so you can hear and tune to it.
Can I change the tuning reference?
It uses the standard 440 Hz for A4, the modern concert pitch.
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