Bolt Threads per Inch (in)
| Bolt Threads per Inch (in) | |||
|---|---|---|---|
| Bolt Size | Threads per Inch | ||
| Course Threads (UNC) | Fine Threads (UNF) | Extra-Fine Threads (UNEF) | |
| #0000 | - | 160 | - | 
| #000 | - | 120 | - | 
| #00 | - | 90 | - | 
| #0 | - | 80 | - | 
| #1 | 64 | 72 | - | 
| #2 | 56 | 64 | - | 
| #3 | 48 | 56 | - | 
| #4 | 40 | 48 | - | 
| #5 | 40 | 44 | - | 
| #6 | 32 | 40 | - | 
| #8 | 32 | 36 | - | 
| #10 | 24 | 32 | - | 
| #12 | 24 | 28 | - | 
| 1/4 | 20 | 28 | 32 | 
| 5/16 | 18 | 24 | 32 | 
| 3/8 | 16 | 24 | 32 | 
| 7/16 | 14 | 20 | 28 | 
| 1/2 | 13 | 20 | 28 | 
| 9/16 | 12 | 18 | 24 | 
| 5/8 | 11 | 18 | 24 | 
| 3/4 | 10 | 16 | 20 | 
| 7/8 | 9 | 14 | 20 | 
| 1 | 8 | 12 | 20 | 
| 1 1/8 | 7 | 12 | 18 | 
| 1 1/4 | 7 | 12 | 18 | 
| 1 3/8 | 6 | 12 | 18 | 
| 1 1/2 | 6 | 12 | 18 | 
| 1 5/8 | - | - | 18 | 
| 1 3/4 | 5 | - | - | 
| 2 | 4 1/2 | - | - | 
| 2 1/4 | 4 1/2 | - | - | 
| 2 1/2 | 4 | - | - | 
| 2 3/4 | 4 | - | - | 
| 3 | 4 | - | - | 
| 3 1/4 | 4 | - | - | 
| 3 1/2 | 4 | - | - | 
| 3 3/4 | 4 | - | - | 
| 4 | 4 | - | - | 
