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Quarter comma meantone is the tuning of meantone temperament which makes the fifth the fourth root of 5, or in other words 696.578 cents. This means the fifth is flattened by 1/4 of the syntonic comma (81/80 ratio) of 21.506 cents, which is to say by 5.377 cents, hence the name quarter-comma or 1/4-comma meantone. It is also the tuning where the major tone is the exact logarithmic average (e.g. cents average) between the greater tone of 9/8 and the lesser tone of 10/9, and hence it can be argued it is the only tuning which is strictly "mean tone" but not the only tuning where the syntonic comma "meant one". It is the minimax tuning for 5-limit meantone, meaning the maximum error on the 5-limit diamond is minimized. It is also the minimax tuning for septimal meantone in the 7- and 9-limit odd limits, and for meanpop, the version of 11-limit meantone which tunes 11/8 to the doubly diminished fifth, C-Gbb. Moreover, historically it was the predominant tuning of Western common-practice music in the latter part of the Renaissance and the early modern (17th century) era.

Because of all of these features, it has a certain claim to be considered the canonical meantone tuning and often "meantone" is taken to mean quarter-comma specifically. The traditional interval names, listed below, may be considered to have their older traditional tuning in the quarter-comma meantone tunings listed below. However, other tunings (besides 12edo which is ubiquitous but not an especially good tuning for meantone) may be preferred. Note, for instance, that the doubly augmented second and the doubly diminished fourth are both neutral thirds, about six cents apart. If we want a tuning which will equate the two, we need to use 31edo instead.

Intervals of quarter-comma meantone[edit]

Below is a table listing 36 of the notes of quarter-comma meantone, giving the size in cents, the number of fifths up or down on the chain of fifths, the letter notation for the interval relative to C as the tonic, the traditional name for the interval, a shorthand form of the name, and the size of the interval in fractional monzo notation.

Size in cents	Fifths dist.	Note C-based	Traditional Interval name	Int. (short)	Fract. Monzo
0	0	C	Unison	P1	[0 0 0>
41.0590	-12	Dbb	Diminished second, diesis	d2	[7 0 -3>
76.0490	7	C#	Augmented unison, chromatic semitone	A1	[-4 0 7/4>
117.108	-5	Db	Minor second, diatonic semitone	m2	[3 0 -5/4>
152.098	14	C##	Augmented chromatic semitone		[-8 0 7/2>
158.167	-17	Ebbb	Doubly diminished third		[10 0 -17/4>
193.157	2	D	Major second	M2	[-1 0 1/2>
234.216	-10	Ebb	Diminished third	d3	[6 0 -5/2>
269.206	9	D#	Augmented second	A2	[-5 0 9/4>
310.265	-3	Eb	Minor third	m3	[2 0 -3/4>
345.255	16	D##	Doubly augmented second		[-9 0 4>
351.324	-15	Fbb	Doubly diminished fourth		[9 0 -15/4>
386.314	4	E	Major third	M3	[-2 0 1>
427.373	-8	Fb	Diminished fourth	d4	[5 0 -2>
462.363	11	E#	Augmented third	A3	[-6 0 11/4>
503.422	-1	F	"Perfect" fourth	P4	[1 0 -1/4>
544.480	-13	Gbb	Doubly diminished fifth		[8 0 -13/4>
579.471	6	F#	Augmented fourth	A4	[-3 0 3/2>
620.529	-6	Gb	Diminished fifth	d5	[4 0 -3/2>
655.520	13	F##	Doubly augmented fourth		[-7 0 13/4>
696.578	1	G	"Perfect" fifth	P5	[0 0 1/4>
737.637	-11	Abb	Diminshed sixth	d6	[7 0 -11/4>
772.627	8	G#	Augmented fifth	A5	[-4 0 2>
813.686	-4	Ab	Minor sixth	m6	[3 0 -1>
848.676	15	G##	Doubly augmented fifth		[-8 0 15/4>
854.745	-16	Bbbb	Doubly diminished seventh		[10 0 -4>
889.735	3	A	Major sixth	M6	[-1 0 3/4>
930.794	-9	Bbb	Diminished seventh	d7	[6 0 -9/4>
965.784	10	A#	Augmented sixth	A6	[-5 0 5/2>
1006.84	-2	Bb	Minor seventh	m7	[2 0 -1/2>
1041.83	17	A##	Doubly augmented sixth		[-9 0 17/4>
1047.90	-14	C'bb	Doubly diminished octave		[9 0 -7/2>
1082.89	5	B	Major seventh	M7	[-2 0 5/4>
1123.95	-7	C'b	Diminished octave	d8	[5 0 -7/4>
1158.94	12	B#	Augmented seventh	A7	[-6 0 3>
1200	0	C'	Perfect octave	P8	[1 0 0>