Middle C Frequency — C4 at 261.63 Hz
Middle C is C4, and in equal temperament with A4 = 440 Hz it sounds at 261.63 Hz. It is MIDI note 60, it sits on the ledger line between the treble and bass staves, and it is the note most beginners are taught to find first. Despite the simple answer, “middle C” is the source of a lot of confusion — mostly because manufacturers cannot agree what to call it.
Middle C at a glance
| Property | Value |
|---|---|
| Frequency | 261.63 Hz |
| MIDI note number | 60 |
| Scientific pitch notation | C4 |
| Yamaha / some DAW labelling | C3 |
| Octave below (C3) | 130.81 Hz |
| Octave above (C5, “tenor C”) | 523.25 Hz |
| Period of one cycle | 3.8223 ms |
Is middle C called C3 or C4?
Both, depending on who you ask — and it is purely a naming difference. The note and its frequency are identical.
- C4 — scientific pitch notation, used by most notation software, by acoustic science, and by Roland. In this system octaves start at C, and middle C begins the fourth octave, hence C4.
- C3 — Yamaha, and software that follows it, count the first piano octave as starting one lower, so the same key lands an octave number down.
This is why a MIDI file can look right in one program and an octave out in another. If you are comparing MIDI note numbers, always use the number: middle C is MIDI 60, unambiguously.
Is middle C actually in the middle of the piano?
Very nearly. An 88-key piano spans A0 to C8. Middle C (C4) is the 40th key from the left, so it sits just left of the physical centre of the keyboard — close enough that the name holds up, and it is roughly the middle of the range most music actually uses.
Where middle C came from
The term predates the modern numbering. In Renaissance and early keyboard music the range of the human voice defined the clefs, and the C clef could be placed on several lines. The C that sat most comfortably between the treble G clef and the bass F clef ended up in the middle of the great stave — and the name stuck.
Frequently asked questions
- What is the frequency of middle C?
- Middle C (C4, MIDI 60) is 261.63 Hz in equal temperament with A4 = 440 Hz.
- Is middle C C3 or C4?
- Both names are used for the same key. Scientific pitch notation and Roland call it C4; Yamaha and some DAWs call it C3. The frequency is identical — and the MIDI number is always 60, which is the safest thing to quote.
- What MIDI number is middle C?
- Middle C is MIDI note 60. MIDI numbers run 0–127, with A4 = 440 Hz at 69.
- How far is middle C from A4?
- Middle C is nine semitones below A4. In frequency that is 261.63 Hz against 440.00 Hz, a ratio of 1.6818.
- What are the C notes either side of middle C?
- C3 is 130.81 Hz, one octave below middle C, and C5 is 523.25 Hz, one octave above. C5 is sometimes called tenor C.
Last updated: 2026-09-01