Intervals are named by the number of scale steps between notes (seconds, thirds, fourths, fifths, sixths, sevenths, and octaves) combined with quality modifiers (major, minor, perfect, diminished, or augmented). For example, the distance from C to G is a Perfect 5th (7 semitones)—the foundational interval of the Circle of Fifths. The distance from C to E is a Major 3rd (4 semitones), which gives major chords their bright character.
KEY TAKEAWAYS- Minor 2nd (1 semitone): Strong dramatic tension.
- Major 3rd vs Minor 3rd (4 vs 3 semitones): The emotional heart of chord construction.
- Perfect 5th (7 semitones): The cornerstone of harmony and key relationships.
- Octave (12 semitones): The exact harmonic double of the root note.
Click through the Chord Lab triads below the scale explorer to hear how stacking thirds creates rich three-note harmony.
Open the scale explorer ↗Connecting Theory to Sound
Music theory is not an abstract set of rules—it is the vocabulary that describes what makes your favorite songs sound so resonant. Use our interactive instruments to hear each concept in real time, and return whenever you want to explore new musical keys.