How to use
Choose distance between notes to compare two pitches, including their octaves. Choose transpose by semitones to move the starting note up with a positive number or down with a negative number.
The output uses scientific pitch notation. In transpose mode it shows common sharp and flat spellings when they differ, so the sounding pitch is clear without claiming a harmonic spelling for your key.
Chromatic calculation
Each adjacent piano key is one semitone. The calculator maps each note to MIDI, subtracts the starting value from the destination, and preserves the sign. Twelve semitones equal one octave.
C4 to G4 is +7 semitones. C5 to A4 is −3 semitones. Transposing Bb3 by +2 gives C4. Octave numbers matter: C4 to C5 is 12, not zero.
Enharmonics and interval names
C#4 and Db4 map to the same equal-tempered pitch and therefore have a chromatic distance of zero. They are still different spellings that can serve different harmonic roles.
A formal interval name depends on both letter spelling and semitone size. For example, augmented and diminished intervals can share a semitone count. This tool deliberately reports semitone distance rather than naming that theory interval.
Limits
- Notes must include an octave and remain within MIDI 0–127.
- Only integer semitone transposition is supported; cents and alternative tunings are excluded.
- The tool does not transpose chords, key signatures, notation files, or uploaded songs.
- Choose the musically correct enharmonic spelling for your score after calculating the pitch.
Frequently asked questions
Does zero semitones mean the names are identical?
Not necessarily. C#4 and Db4 have zero chromatic distance in equal temperament but retain different spellings.
Is seven semitones always called a perfect fifth?
Not from semitone count alone. A formal interval name also depends on the written letter names, which this calculator deliberately does not infer.