4:5:6

4:5:6 is the classical major triad, also known as the Ptolemaic major triad, or, imprecisely, as the just major triad. It is the most consonant of all the just intonation triads.

Chord information

Harmonics	4:5:6
Subharmonics	1/(15:12:10)
Intervals from root	1/1–5/4–3/2
Cents from root	0¢–386¢–702¢
Step intervals	5/4, 6/5
Step cents	386¢, 316¢
Color name	yo or y
Prime limit	5
Genus	3⋅5 (15)
Intervallic odd limit	5
Otonal odd limit	5
Utonal odd limit	15
Consistent edos (d ≥ 2)	3edo*, 12edo*, 15edo*, 19edo**, …
* 2 ≤ d < 4; ** 4 ≤ d < 8; *** 8 ≤ d < 16; …

Common tetrads based on this triad (5-limit except where noted):

• 12:15:18:20 adds 5/3
• 8:10:12:15 adds 15/8
• 36:45:54:64 adds 16/9
• 20:25:30:36 adds 9/5
• 4:5:6:7 adds 7/4 (7-limit)