Frequency & Pitch Converter
Hz, note name, cents, MIDI — convert from any, to all.
Four representations, one pitch
Any pitch can be described four ways: as a frequency in Hz, as a note name with cents offset, as a MIDI note number, or as cents from a reference. Calcophony lets you enter one and immediately see the other three. Type 466.16 and watch it resolve to A♯4 / B♭4, MIDI 70, 0 cents from equal temperament. Type "C4 +10¢" and see 264.14 Hz, MIDI 60.1. No sequence of taps, no modal state — every field is an input.
What you can enter
- Frequency — in Hz, any positive number within the audible range and beyond.
- Note name — C4, A♭3, F♯5, with or without an explicit cents offset.
- MIDI note — integer or fractional (e.g. 69.5 for A4 + 50 cents).
- Cents — from an arbitrary reference pitch.
Options
- Reference pitch — A4 from 415 Hz (historical baroque) through 440 Hz (ISO standard) to 442–444 Hz (modern orchestral). Every conversion respects this reference.
- Enharmonic spelling — toggle between sharp and flat note names.
- Reference tone playback — audition the current pitch as a sine wave.
When to use it
Setting up a synth patch where the oscillator wants Hz but the composer thinks in note names. Debugging an analog filter that's drifting and you need to know the cent error. Preparing parts for an ensemble tuned to 415 Hz. Converting a measured peak frequency from a spectrum analyzer into a pitch a player can actually tune to. For comparing the same interval across multiple tuning systems, use Interval & Tuning.