MusicReasonProduction, Synthesis, and Audio Math
What note is this MIDI number?
Enter a MIDI number (0-127) or a note name. This tool converts between MIDI number, note name, octave, and frequency under an explicit A4 reference.
Answer
Want to learn more? MIDI Notes, Pitch Bend, and Musical Pitch Data
Understand
MIDI note numbering is a fixed convention: MIDI 60 is always C4 (middle C) and MIDI 69 is always A4, regardless of your chosen A4 reference frequency. Changing the A4 reference changes the resulting Hz value, never the note-to-number mapping itself.
Worked examples
MIDI 60 is C4. MIDI 69 is A4, 440 Hz at the default reference. MIDI 127, the top of the standard range, is accepted as a valid boundary value.
Method and limitations
Frequency uses the shared formula A4 × 2^((m−69)/12). This tool covers the standard MIDI 0-127 note range only; it does not encode MIDI 2.0 microtonal extensions or any device-specific program or channel mapping.
A convention worth knowing by heart
MIDI note numbers show up constantly in sequencer piano-roll displays, sample-mapping editors, and scripting APIs, almost always as bare integers with no note name attached. Being able to translate MIDI 60 to C4 and back without a reference chart saves real time when reading a patch's key-range settings or debugging a MIDI file's raw event data.
One recurring point of confusion is that "octave 4" in scientific pitch notation (C4 as middle C) is not universally what every DAW or synth displays: some vendors label the same MIDI note as C3 or C5 depending on their own octave-numbering choice. This tool follows the scientific-pitch convention shared across the rest of MusicReason, so the octave number it reports may differ by one from a specific product's own display, even though the underlying MIDI number and frequency are identical either way.