Convert between MIDI numbers, note names and frequencies
MIDI note number (0–127)
Note name (e.g. C4, A#3, Bb5)
C4
MIDI 60 · 261.63 Hz · Middle C
60
MIDI number
261.63 Hz
Frequency
4
Octave
131.87 cm
Wavelength
Instrument ranges
Full MIDI reference (0–127) — click any row
MIDI
Note
Freq (Hz)
Octave
Instruments
Frequently asked questions
What MIDI note number is middle C?
Middle C is MIDI note 60. It is C in the 4th octave (C4) with a frequency of 261.63 Hz at A4 = 440 Hz. Note 60 is the most referenced MIDI note in music production.
What is the MIDI note number range?
MIDI notes run from 0 (C-1, ~8 Hz) to 127 (G9, ~12,543 Hz). A standard 88-key piano covers MIDI notes 21 (A0) to 108 (C8).
How do MIDI note numbers relate to octaves?
Each octave spans 12 MIDI notes. The formula is: octave = floor(note ÷ 12) − 1. So note 60: floor(60 ÷ 12) − 1 = 5 − 1 = octave 4, which gives C4 (middle C).