F4
349.228Hz at concert pitch
Press to hear a pure sine tone at this pitch.
MIDI note
65
Piano key
45
Octave
4
Frequency
349.228 Hz
Period
2.8635 ms
Wavelength
0.9822 m
Pitch class
F
Notation
SPN
MIDI is the note number synths and software pass around (0–127). Pitch class is the note without its octave — all the Fs share one.
At other reference pitches
| Reference (A4) | F4 frequency | Where you meet it |
|---|---|---|
| 432 Hz | 342.879 Hz | the alternative-tuning circle |
| 440 Hzstandard | 349.228 Hz | the ISO 16 standard — concert pitch |
| 442 Hz | 350.816 Hz | many European orchestras tune a touch sharp |
| 443 Hz | 351.609 Hz | some sharper continental orchestras |
Every row is F4 — only the A4 you tune to changes. A frequency scales straight with the reference: F4 at 432 Hz is the 440 Hz value times 432⁄440.
Move around
Every F
Chords with F in them
F appears in each of these — see the whole chord grid.