12UN and 12UNR Fixed Pitch Series Thread Chart

Measured in Inches
Size Primary
Inch		 Basic Major Diameter
Inch		 Basic Pitch Diameter
Inch		 Minor Diameter, inch Minor Dia. Area
sq. inch
Tensile Stress Area
sq. inch
External Thread Internal Thread
9/16 0.5625 0.5084 0.4633 0.4723 0.162 0.182
5/8 0.625 0.5709 0.5258 0.5348 0.21 0.232
11/16 0.6875 0.6334 0.5883 0.5973 0.264 0.289
3/4 0.75 0.6959 0.6508 0.6598 0.323 0.351
13/16 0.8125 0.7584 0.7133 0.7223 0.39 0.42
7/8 0.875 0.8209 0.7758 0.7848 0.462 0.495
15/16 0.9375 0.8834 0.8383 0.8473 0.54 0.576
1 1 0.9459 0.9008 0.9098 0.625 0.663
1 - 1/6 1.0625 1.0084 0.9633 0.9723 0.715 0.756
1 - 1/8 1.125 1.0709 1.0258 1.0348 0.812 0.856
1 - 3/16 1.1875 1.1334 1.0883 1.0973 0.915 0.961
1 - 1/4 1.25 1.1959 1.1508 1.1598 1.024 1.073
1 - 5/16 1.3125 1.2584 1.2133 1.2223 1.139 1.191
1 - 3/8 1.375 1.3209 1.2758 1.2848 1.26 1.315
1 - 7/16 1.4375 1.3834 1.3383 1.3473 1.388 1.445
1 - 1/2 1.5 1.4459 1.4008 1.4098 1.52 1.58
1 - 9/16 1.5625 1.5084 1.4633 1.4723 1.66 1.72
1 - 5/8 1.625 1.5709 1.5258 1.5348 1.81 1.87
1 - 11/16 1.6875 1.6334 1.5883 1.5973 1.96 2.03
1 - 3/4 1.75 1.6959 1.6508 1.6598 2.12 2.19
1 - 13/16 1.8125 1.7584 1.7133 1.7223 2.28 2.35
1 - 7/8 1.875 1.8209 1.7758 1.7848 2.45 2.53
1 - 15/16 1.9375 1.8834 1.8383 1.8473 2.63 2.71
2 2 1.9459 1.9008 1.9098 2.81 2.89
2 - 1/8 2.125 2.0709 2.0258 2.0348 3.19 3.28
2 - 1/4 2.25 2.1959 2.1508 2.1598 3.6 3.69
2 - 3/8 2.375 2.3209 2.2758 2.2848 4.04 4.13
2 - 1/2 2.5 2.4459 2.4008 2.4098 4.49 4.6
2 - 5/8 2.625 2.5709 2.5258 2.5348 4.97 5.08
2 - 3/4 2.75 2.6959 2.6508 2.6598 5.48 5.59
2 - 7/8 2.875 2.8209 2.7758 2.7848 6.01 6.13
3 3 2.9459 2.9008 2.9098 6.57 6.69
3 - 1/8 3.125 3.0709 3.0258 3.0348 7.15 7.28
3 - 1/4 3.25 3.1959 3.1508 3.1598 7.75 7.89
3 - 3/8 3.375 3.3209 3.2758 3.2848 8.38 8.52
3 - 1/2 3.5 3.4459 3.4008 3.4098 9.03 9.18
3 - 5/8 3.625 3.5709 3.5258 3.5348 9.71 9.86
3 - 3/4 3.75 3.6959 3.6508 3.6598 10.42 10.57
3 - 7/8 3.875 3.8209 3.7758 3.7848 11.14 11.3
4 4 3.9459 3.9008 3.9098 11.9 12.06
4 - 1/8 4.125 4.0709 4.0258 4.0348 12.67 12.84
4 - 1/4 4.25 4.1959 4.1508 4.1598 13.47 13.65
4 - 3/8 4.375 4.3209 4.2758 4.2848 14.3 14.48
4 - 1/2 4.5 4.4459 4.4008 4.4098 15.1 15.3
4 - 5/8 4.625 4.5709 4.5258 4.5348 16 16.2
4 - 3/4 4.75 4.6959 4.6508 4.6598 16.9 17.1
4 - 7/8 4.875 4.8209 4.7758 4.7848 17.8 18
5 5 4.9459 4.9008 4.9098 18.8 19
5 - 1/8 5.125 5.0709 5.0258 5.0348 19.8 20
5 - 1/4 5.25 5.1959 5.1508 5.1598 20.8 21
5 - 3/8 5.375 5.3209 5.2758 5.2848 21.8 22
5 - 1/2 5.5 5.4459 5.4008 5.4098 22.8 23.1
5 - 5/8 5.625 5.5709 5.5258 5.5348 23.9 24.1
5 - 3/4 5.75 5.6959 5.6508 5.6598 25 25.2
5 - 7/8 5.875 5.8209 5.7758 5.7848 26.1 26.4
6 6 5.9459 5.9008 5.9098 27.3 27.5