F2
87.307Hz at concert pitch
Press to hear a pure sine tone at this pitch.
MIDI note
41
Piano key
21
Octave
2
Frequency
87.307 Hz
Period
11.4538 ms
Wavelength
3.9287 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) | F2 frequency | Where you meet it |
|---|---|---|
| 432 Hz | 85.72 Hz | the alternative-tuning circle |
| 440 Hzstandard | 87.307 Hz | the ISO 16 standard — concert pitch |
| 442 Hz | 87.704 Hz | many European orchestras tune a touch sharp |
| 443 Hz | 87.902 Hz | some sharper continental orchestras |
Every row is F2 — only the A4 you tune to changes. A frequency scales straight with the reference: F2 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.