Bolt & Screw Thread Pitches
Imperial / Inch Thread Pitch Chart
Diameter | UNC | UNF | 8-UN |
#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 | - |
5/16" | 18 | 24 | - |
3/8" | 16 | 24 | - |
7/16" | 14 | 20 | - |
1/2" | 13 | 20 | - |
9/16" | 12 | 18 | - |
5/8" | 11 | 18 | - |
3/4" | 10 | 16 | - |
7/8" | 9 | 14 | - |
1" | 8 | 12 (Special) 14 (Common) |
- |
1-1/8" | 7 | 12 | 8 |
1-1/4" | 7 | 12 | 8 |
1-3/8" | 6 | 12 | 8 |
1-1/2" | 6 | 12 | 8 |
1-3/4 | 5 | - | 8 |
2" | 4-1/2 | - | 8 |
2-1/4" | 4-1/2 | - | 8 |
2-1/2" | 4 | - | 8 |
2-3/4" | 4 | - | 8 |
3" | 4 | - | 8 |
3-1/4" | 4 | - | 8 |
3-1/2" | 4 | - | 8 |
3-3/4" | 4 | - | 8 |
4" | 4 | - | 8 |
Metric / mm Thread Pitch Chart
Diameter | Coarse | Fine | Fine (2/3/4) |
M1 | 0.25 | - | - |
M1.2 | 0.25 | - | - |
M1.4 | 0.3 | - | - |
M1.6 | 0.35 | - | - |
M1.8 | 0.35 | - | - |
M2 | 0.4 | - | - |
M2.5 | 0.45 | - | - |
M3 | 0.5 | - | - |
M3.5 | 0.6 | - | - |
M4 | 0.7 | - | - |
M5 | 0.8 | 0.9 | 0.75 / 0.5 |
M6 | 1 | 0.75 | 0.5 |
M7 | 1 | 0.75 | 0.5 |
M8 | 1.25 | 1 | 0.75 / 0.5 |
M10 | 1.5 | 1.25 | 1 / 0.75 |
M12 | 1.75 | 1.5 | 1.25 / 1 |
M14 | 2 | 1.5 | 1.25 / 1 |
M16 | 2 | 1.5 | 1 |
M18 | 2.5 | 2 | 1.5 / 1 |
M20 | 2.5 | 2 | 1.5 / 1 |
M22 | 2.5 | 2 | 1.5 / 1 |
M24 | 3 | 2 | 1.5 / 1 |
M27 | 3 | 2 | 1.5 / 1 |
M30 | 3.5 | 3 | 2 / 1.5 / 1 |
M33 | 3.5 | 3 | 2 / 1.5 |
M36 | 4 | 3 | 2 / 1.5 |
M39 | 4 | 3 | 2 / 1.5 |
M42 | 4.5 | 4 | 3 / 2 / 1.5 |
M45 | 4.5 | 3 | - |
M48 | 5 | 3 | - |
M52 | 5 | 4 | - |
M56 | 5.5 | 4 | - |
M60 | 5.5 | 4 | - |
M64 | 6 | 4 | - |