C4 frequency
In standard tuning (A4 = 440 Hz), C4 is 261.63 Hz. This is middle C. It's MIDI note 60 and key 40 of 88 on a piano.
| Frequency | 261.63 Hz |
| Period | 3.822 ms |
| Wavelength in air | 1.31 m |
| One octave down | C3 · 130.81 Hz |
| One octave up | C5 · 523.25 Hz |
| At A4 = 432 Hz | 256.87 Hz |
C4 is within the usual range of piano, guitar, bass guitar, violin, viola, cello, flute, trumpet, ukulele, a bass voice, a tenor voice, an alto voice and a soprano voice.
See every note on the note frequency chart, or train your ear to recognise notes like this one in the course.
Questions
What is the frequency of C4?
261.63 Hz in standard tuning, where A4 is 440 Hz.
What is C4 at 432 Hz tuning?
If A4 is tuned to 432 Hz, C4 becomes 256.87 Hz.
Which octave is C4 in?
Octave 4. Octaves are numbered from C, so C4 sits above middle C (C4).
More free tools
Online tuner · Online metronome · BPM tapper · Interval ear training · Chord ear training · Tone deaf test · Vocal range test · Note frequency chart · Binaural beats generator · Frequency sweep generator · White, pink & brown noise · Tone generator · Perfect pitch test · Hearing test