Perfect 5th
Perfect 5th: Eb – Bb, 7 semitones; perfect consonance.
Theory
General info
- Interval
- Perfect 5th
- Quality
- Perfect
- Semitones
- 7
- Degree distance
- 5 degrees
- Degree
- 5
Interval structure
- Lower note
- Eb (311.1 Hz)
- Lower note role
- Root
- Upper note
- Bb (466.2 Hz)
- Upper note role
- Perfect fifth (5)
- Degree formula
- IV
- Semitone formula
- 7 semitones (3.5 tones)
Interval construction
- Interval formula
- P5
- Brief explanation
- A perfect fifth spans seven semitones and is a perfect consonance. It belongs to major and minor triads and, together with the root, forms a power chord.
Interval notes
Consonance / dissonance
- Sonority
- Perfect consonance
- Explanation
- A perfect fifth is a perfect consonance. Without a third, it defines neither major nor minor quality, so the sonority sounds open and mode-neutral.
How the interval sounds
A perfect fifth spans seven semitones and is a perfect consonance. It belongs to major and minor triads; without a third, it forms a power chord with no major or minor quality.
Famous example:
- The "Star Wars" theme
Tendencies & resolutions
As a consonance, a fifth requires no resolution by itself. Root motion by fifth has a separate role: V – I in the bass, usually up a fourth or down a fifth, forms the basis of an authentic cadence.
Harmonic context
The 5th is the interval between degrees I and V. It appears in maj and min triads, in 7, maj7, and m7 chords. The circle of fifths — the foundation of the tonal system — is built on a chain of 5ths. In power chords, the 5th is the only interval besides the root. In medieval music, parallel 5ths were the basis of polyphony (organum).
Interval inversion
- Inverts to
- Perfect 4th
- Quality change
- Perfectperfect
- Inversion rule
- When inverting a perfect 5th, the lower note moves up an octave. 7 semitones (P5) become 5 semitones — a perfect 4th (P4).
Related intervals
How to play on piano
This interval on guitar 🎸
See how Perfect 5th looks on guitar.