Unified Thread Series 12 TPI ANSI/ASME B1.1

12-UN - Unified Extra Fine Thread, which is used for special purposes.
The flank angle is 60°.

Nominal
Diameter
Major
Diameter
Inch
Major
Diameter
mm
Tapping
Drill Size
mm
TPI Pitch
mm
5/8" - 12-UN 0.6250 15.875 13.900 12 2.117
11/16" - 12-UN 0.6875 17.462 15.500 12 2.117
3/4" - 12-UN 0.7500 19.050 17.000 12 2.117
13/16" - 12-UN 0.8125 20.637 18.600 12 2.117
7/8" - 12-UN 0.8750 22.225 20.200 12 2.117
15/16" - 12-UN 0.9375 23.813 21.800 12 2.117
1 1/16" - 12-UN 1.0625 26.987 25.000 12 2.117
1 3/16" - 12-UN 1.1875 30.162 28.200 12 2.117
1 5/16" - 12-UN 1.3125 33.337 31.300 12 2.117
1 7/16" - 12-UN 1.4375 36.512 34.500 12 2.117
1 9/16" - 12-UN 1.5625 39.688 37.700 12 2.117
1 5/8" - 12-UN 1.6250 41.275 39.300 12 2.117
1 11/16" - 12-UN 1.6875 42.862 40.850 12 2.117
1 3/4" - 12-UN 1.7500 44.450 42.400 12 2.117
1 13/16" - 12-UN 1.8125 46.037 44.000 12 2.117
1 7/8" - 12-UN 1.8750 47.625 45.600 12 2.117
1 15/16" - 12-UN 1.9375 49.212 47.200 12 2.117
2" - 12-UN 2.0000 50.800 48.800 12 2.117
2 1/8" - 12-UN 2.1250 53.975 52.000 12 2.117
2 1/4" - 12-UN 2.2500 57.150 55.100 12 2.117
2 3/8" - 12-UN 2.3750 60.325 58.300 12 2.117
2 1/2" - 12-UN 2.5000 63.500 61.500 12 2.117
2 5/8" - 12-UN 2.6250 66.675 64.700 12 2.117
2 3/4" - 12-UN 2.7500 69.850 67.800 12 2.117
2 7/8" - 12-UN 2.8750 73.025 71.000 12 2.117
3" - 12-UN 3.0000 76.200 74.200 12 2.117
3 1/8" - 12-UN 3.1250 79.375 77.400 12 2.117
3 1/4" - 12-UN 3.2500 82.550 80.500 12 2.117
2 3/8" - 12-UN 3.3750 85.725 83.700 12 2.117
3 1/2" - 12-UN 3.5000 88.900 86.900 12 2.117
3 5/8" - 12-UN 3.6250 92.075 90.100 12 2.117
3 3/4" - 12-UN 3.7500 95.250 93.250 12 2.117
3 7/8" - 12-UN 3.8750 98.425 96.400 12 2.117
4" - 12-UN 4.0000 101.600 99.600 12 2.117
4 1/8" - 12-UN 4.1250 104.775 102.800 12 2.117
4 1/4" - 12-UN 4.2500 107.950 105.900 12 2.117
4 3/8" - 12-UN 4.3750 111.125 109.100 12 2.117
4 1/2" - 12-UN 4.5000 114.300 112.300 12 2.117
4 5/8" - 12-UN 4.6250 117.475 115.500 12 2.117
4 3/4" - 12-UN 4.7500 120.650 118.700 12 2.117
4 7/8" - 12-UN 4.8750 123.825 121.700 12 2.117
5" - 12-UN 5.0000 127.000 125.000 12 2.117
5 1/8" - 12-UN 5.1250 130.175 128.200 12 2.117
5 1/4" - 12-UN 5.2500 133.350 131.400 12 2.117
5 3/8" - 12-UN 5.3750 136.525 134.500 12 2.117
5 1/2" - 12-UN 5.5000 139.700 137.700 12 2.117
5 5/8" - 12-UN 5.6250 142.875 140.900 12 2.117
5 3/4" - 12-UN 5.7500 146.050 144.000 12 2.117
6" - 12-UN 6.0000 152.400 150.400 12 2.117