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Note Frequency Chart
Look up the frequency of any note across the octaves, with adjustable concert pitch and the cents deviation between tuning systems.
🔒 This tool runs entirely in your browser. Your files are never uploaded to a server.
Audio
Note Frequency Chart
Frontend preview — no upload or external service.
Frequency
A4 = 440.00 Hz, A5 = 880.00, A3 = 220.00. At the baroque pitch of 415 Hz, A4 sits about 100 cents — a full semitone — below modern concert pitch.
How the Note Frequency Chart works
- Pick the note and octave using scientific pitch notation, where middle C is C4.
- Set the concert pitch reference if you are not working at A440.
- Read the cents deviation when comparing systems; a hundred cents is one semitone.
The method
In equal temperament each semitone multiplies frequency by the twelfth root of two, so an octave exactly doubles it.
f = 440 × 2^(n/12), where n is semitones from A4
A5 is twelve semitones up: 440 × 2 = 880 Hz. The twelfth root of two is about 1.0595, which is the ratio between any two adjacent semitones.
FAQ
Why is A440 the standard?
It was adopted as an international standard in the twentieth century, replacing a range of local pitches. Orchestras still vary slightly around it, and some tune deliberately sharper for brightness.
What is a cent?
A hundredth of a semitone — 1200 cents to the octave. It is a logarithmic unit, which means a cent represents the same perceived interval anywhere in the range, unlike a fixed number of hertz.
Why is equal temperament a compromise?
Because it makes every key equally usable by making no interval except the octave perfectly in tune. Just intonation gives purer thirds and fifths in one key and unusable intervals in others.
How we compare
| Feature | Online Tool Store | A DAW | A streaming app |
|---|---|---|---|
| Adjustable concert pitch | ✓ | Fixed | Yes |
| Cents deviation shown | ✓ | ✗ | Sometimes |
| No account | ✓ | ✓ | ✗ |
| Works offline once loaded | ✓ | ✓ | ✗ |
Note Frequency Chart shows cents alongside hertz, because a fixed frequency difference means a different musical interval at every pitch.