P4

Perfect · 5 semitones

Perfect 4th

Five semitones — open, stable, and somewhat hollow. Forms the basis of quartal harmony and is heard in many traditional folk melodies.

perfect5 semitonesP4

How to Hear It

How to Identify It

Open and somewhat suspended — not quite as resolved as a 5th. Think of Here Comes the Bride (Wagner) — the opening leap is a perfect 4th. Or Amazing Grace.

Famous Examples

  • Here Comes the Bride (Wagner) — opening leap
  • Amazing Grace — first two notes (A-maz-)
  • Auld Lang Syne — opening interval
  • Ein Feste Burg (Bach) — opening
Ready to test your ear?The recognition trainer plays random intervals — identify them by ear with instant feedback.
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Often Confused With

P5
Perfect 5th7 semitones
M3
Major 3rd4 semitones
P1
Unison0 semitones
P8
Octave12 semitones

All Intervals

P1Unison0stm2Minor 2nd1stM2Major 2nd2stm3Minor 3rd3stM3Major 3rd4stP4Perfect 4th5stTTTritone6stP5Perfect 5th7stm6Minor 6th8stM6Major 6th9stm7Minor 7th10stM7Major 7th11stP8Octave12stm9Minor 9th13stM9Major 9th14st

About the Perfect 4th

The Perfect 4th (P4) is a perfect interval spanning 5 semitones. Five semitones — open, stable, and somewhat hollow. Forms the basis of quartal harmony and is heard in many traditional folk melodies.

To train your ear to identify the perfect 4th reliably, practice hearing it in all three modes — ascending, descending, and harmonic. The ascending version is most commonly tested, but recognising it in all contexts is the mark of a trained ear. Use the trainer above to test yourself in a mixed set of all intervals.