Threads Per Inch Reference Table
| Size |
COURSE UNC (USS) |
FINE UNF (SAE) |
BASIC MAJOR DIAMETER |
| 0 |
80 |
.0600 |
|
| 1 |
64 |
72 |
.730 |
| 2 |
56 |
64 |
.0860 |
| 3 |
48 |
56 |
.0990 |
| 4 |
40 |
48 |
.1120 |
| 5 |
40 |
44 |
.1250 |
| 6 |
32 |
40 |
.1380 |
| 8 |
32 |
36 |
.1640 |
| 10 |
24 |
32 |
.1900 |
| 12 |
24 |
28 |
.2160 |
| 1/4 |
20 |
28 |
.2500 |
| 5/16 |
18 |
24 |
.3125 |
| 3/8 |
16 |
24 |
.3750 |
| 7/16 |
14 |
20 |
.4375 |
| 1/2 |
13 |
20 |
.500 |
| 9/16 |
12 |
18 |
.5625 |
| 5/8 |
11 |
18 |
.6250 |
| 3/4 |
10 |
16 |
.7500 |
| 7/8 |
9 |
14 |
.8750 |
| 1 |
8 |
12 / 14 |
1.000 |
| 1-1/8 |
7 |
12 |
1.125 |
| 1-1/4 |
7 |
12 |
1.250 |
| 1-3/8 |
6 |
12 |
1.375 |
| 1-1/2 |
6 |
12 |
1.500 |
| 1-5/8 |
5-1/2 |
1.625 |
|
| 1-3/4 |
5 |
1.750 |
|
| 1-7/8 |
5 |
1.875 |
|
| 2 |
4-1/2 |
2 |
|
| 2-1/4 |
4-1/2 |
2.250 |
|
| 2-1/2 |
4 |
2.500 |
|
| 2-3/4 |
4 |
2.750 |
|
| 3 |
4 |
3 |
|
| 3-1/4 |
4 |
3.250 |
|
| 3-1/2 |
4 |
3.500 |
|
| 3-3/4 |
4 |
3.750 |
|
| 4 |
4 |
4.000 |
Picture is a general representation. Dimensions will vary depending on the product size you choose.