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Fraction to decimal and millimeter chart

Every 64th of an inch from 1/64″ to 1″, as a decimal and in millimeters. The sixteenths are bold — the marks on most tapes.

Use it to read a decimal off a caliper or CNC drawing as a tape measurement, or to convert a metric hardware spec. The tape measure calculator works with fractions directly.

Verify with your local code and AHJ. Reference only, no warranty.

0 – 1/4″

	Decimal	mm
1/64	0.0156	0.40
1/32	0.0313	0.79
3/64	0.0469	1.19
1/16	0.0625	1.59
5/64	0.0781	1.98
3/32	0.0938	2.38
7/64	0.1094	2.78
1/8	0.1250	3.17
9/64	0.1406	3.57
5/32	0.1563	3.97
11/64	0.1719	4.37
3/16	0.1875	4.76
13/64	0.2031	5.16
7/32	0.2188	5.56
15/64	0.2344	5.95
1/4	0.2500	6.35

1/4 – 1/2″

	Decimal	mm
17/64	0.2656	6.75
9/32	0.2813	7.14
19/64	0.2969	7.54
5/16	0.3125	7.94
21/64	0.3281	8.33
11/32	0.3438	8.73
23/64	0.3594	9.13
3/8	0.3750	9.52
25/64	0.3906	9.92
13/32	0.4063	10.32
27/64	0.4219	10.72
7/16	0.4375	11.11
29/64	0.4531	11.51
15/32	0.4688	11.91
31/64	0.4844	12.30
1/2	0.5000	12.70

1/2 – 3/4″

	Decimal	mm
33/64	0.5156	13.10
17/32	0.5313	13.49
35/64	0.5469	13.89
9/16	0.5625	14.29
37/64	0.5781	14.68
19/32	0.5938	15.08
39/64	0.6094	15.48
5/8	0.6250	15.88
41/64	0.6406	16.27
21/32	0.6563	16.67
43/64	0.6719	17.07
11/16	0.6875	17.46
45/64	0.7031	17.86
23/32	0.7188	18.26
47/64	0.7344	18.65
3/4	0.7500	19.05

3/4 – 1″

	Decimal	mm
49/64	0.7656	19.45
25/32	0.7813	19.84
51/64	0.7969	20.24
13/16	0.8125	20.64
53/64	0.8281	21.03
27/32	0.8438	21.43
55/64	0.8594	21.83
7/8	0.8750	22.22
57/64	0.8906	22.62
29/32	0.9063	23.02
59/64	0.9219	23.42
15/16	0.9375	23.81
61/64	0.9531	24.21
31/32	0.9688	24.61
63/64	0.9844	25.00
1	1.0000	25.40

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Open this sheet in the toolkit to search it, pin it and use it offline.

Questions

What is 3/8 as a decimal?

0.3750″, or 9.52 mm.

What is 5/16 in millimeters?

7.94 mm (0.3125″).

What fraction is 0.75 inches?

3/4″, which is 19.05 mm.