Tool
Interval calculator
Pick two pitches. The tool counts semitones from the first to the second and names the interval. C4 to G4 is a perfect fifth, seven semitones.
First pitch
Second pitch
When to use the interval calculator
Use this page when you want the chromatic size of a step, not a Roman-numeral analysis. The name comes from the semitone count: m2, M2, m3, M3, P4, A4 / d5, P5, m6, M6, m7, M7, and P8.
Enharmonic spelling follows one rule: an upward chromatic step prefers a sharp. C to C♯ is a minor second. The page does not look up a key signature to choose D♭ instead.
Note names are C, D, E, F, G, A, and B. In some countries the note B is written H; this page uses B.
Worked examples
Seven semitones, P5, a perfect fifth. Can you sing G above C without sliding?
Four semitones, M3, a major third. Does that match the third of a C major triad?
One semitone, m2. The upward spelling is C♯, not D♭, because this page prefers sharps going up.
Questions
What if the second note is lower?
The semitone count is still the absolute distance. The text says the interval is descending from the first pitch.
How are octaves handled?
Twelve semitones are a perfect octave (P8). Wider spans are named as octaves plus the remaining interval.
Is an augmented fourth the same as a diminished fifth here?
Six semitones are both an augmented fourth and a diminished fifth. The page prints both names and does not pick a key.