Note frequency chart
The frequency of every note from C0 to B8 in hertz. Middle C is 261.63 Hz and concert A is 440 Hz. Tap any note to hear it.
| Note | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 |
|---|---|---|---|---|---|---|---|---|---|
| C | |||||||||
| C♯/D♭ | |||||||||
| D | |||||||||
| D♯/E♭ | |||||||||
| E | |||||||||
| F | |||||||||
| F♯/G♭ | |||||||||
| G | |||||||||
| G♯/A♭ | |||||||||
| A | |||||||||
| A♯/B♭ | |||||||||
| B |
Values in Hz, twelve-tone equal temperament. Columns are octaves in scientific pitch notation (C4 = middle C). Highlighted cells: lowest and highest piano keys, guitar low E, middle C and tuning A. Each tap plays a 1.5-second sine tone at a low level.
The formula behind the chart
Every value above comes from one line: f = 440 × 2(n − 69) / 12, where n is the MIDI note number (middle C is 60, A4 is 69). Going up one semitone multiplies the frequency by about 1.0595, so twelve semitones exactly double it. That is why each column is twice the one to its left.
Common reference notes
| Instrument | Open strings (low to high) |
|---|---|
| Guitar, standard tuning | E2 82.41 · A2 110.00 · D3 146.83 · G3 196.00 · B3 246.94 · E4 329.63 |
| Bass guitar, 4-string | E1 41.20 · A1 55.00 · D2 73.42 · G2 98.00 |
| Violin | G3 196.00 · D4 293.66 · A4 440.00 · E5 659.26 |
To hold any of these as a steady reference while you tune, open the tone generator, pick the note from its Musical note list, and tune until the slow beating between string and tone disappears. Fixed pages exist for 440 Hz, 432 Hz and 256 Hz.
Where notes sit in audio terms
The fundamental of most music lives between about 40 Hz (a bass guitar's low E) and 4 kHz (the top of a piano). Above that you hear harmonics, which give instruments their character. A spectrum analyzer shows both: play a note into your mic and the lowest strong peak is the fundamental.
Questions people ask
What is the frequency of middle C?
Middle C (C4) is 261.63 Hz in standard tuning, where A4 = 440 Hz. In "scientific pitch", which some acoustics texts use, C4 is exactly 256 Hz.
Why is A4 440 Hz?
A4 = 440 Hz is the international standard tuning pitch, set out in ISO 16. Before it was agreed, orchestras tuned anywhere from about 415 Hz to over 450 Hz. Some orchestras today tune slightly higher, at 442 or 443 Hz.
How do you calculate a note's frequency?
In twelve-tone equal temperament each semitone multiplies the frequency by the twelfth root of 2 (about 1.05946). The formula is f = 440 × 2^((n − 69) / 12), where n is the MIDI note number (A4 = 69, middle C = 60). Every octave doubles the frequency.
What are the lowest and highest notes on a piano?
A standard 88-key piano runs from A0 at 27.50 Hz to C8 at 4186.0 Hz.
What are the frequencies of the guitar strings?
In standard tuning: E2 82.41 Hz, A2 110.00 Hz, D3 146.83 Hz, G3 196.00 Hz, B3 246.94 Hz and E4 329.63 Hz.
Is 432 Hz tuning better?
It is a valid stylistic choice and sounds slightly lower and darker, but there is no scientific evidence for the health or "natural harmony" claims often attached to it. Switch the chart to A4 = 432 Hz to see the exact values.
Keep testing
- Tone generatorSine, square, triangle and sawtooth from 1 Hz to 22 kHz.
- Multiple tonesUp to six tones at once: beats, chords, IMD and dial tones.
- Spectrum analyzerReal-time FFT of your microphone with peak hold and note readout.