Complete reference for metric and imperial thread specifications including pitch, major diameter, and minor diameter for precision CNC machining.
The largest diameter of the thread, measured from crest to crest across the thread.
The smallest diameter of the thread, measured from root to root across the thread.
Distance between adjacent thread crests. Metric uses mm, imperial uses threads per inch.
| Thread Size | Pitch (mm) | Major Ø (mm) | Minor Ø (mm) | Common Applications |
|---|---|---|---|---|
| M3 | 0.5 | 3.000 | 2.459 | Electronics, small assemblies |
| M4 | 0.7 | 4.000 | 3.242 | Electronics, small hardware |
| M5 | 0.8 | 5.000 | 4.134 | General hardware, automotive |
| M6 | 1.0 | 6.000 | 4.918 | General purpose, automotive |
| M8 | 1.25 | 8.000 | 6.647 | Structural, automotive |
| M10 | 1.5 | 10.000 | 8.376 | Structural, machinery |
| M12 | 1.75 | 12.000 | 10.106 | Heavy duty, structural |
| M16 | 2.0 | 16.000 | 13.835 | Heavy machinery, structural |
| M20 | 2.5 | 20.000 | 17.294 | Heavy machinery, construction |
| Thread Size | TPI | Major Ø (in) | Minor Ø (in) | Common Applications |
|---|---|---|---|---|
| #4-40 | 40 | 0.112 | 0.0813 | Electronics, small hardware |
| #6-32 | 32 | 0.138 | 0.0997 | Electronics, computer hardware |
| #8-32 | 32 | 0.164 | 0.1257 | General hardware, panels |
| #10-24 | 24 | 0.190 | 0.1389 | General hardware, automotive |
| 1/4"-20 | 20 | 0.250 | 0.1887 | General purpose, automotive |
| 5/16"-18 | 18 | 0.3125 | 0.2443 | Automotive, machinery |
| 3/8"-16 | 16 | 0.375 | 0.3344 | Structural, machinery |
| 1/2"-13 | 13 | 0.500 | 0.4056 | Heavy duty, structural |
| 5/8"-11 | 11 | 0.625 | 0.5135 | Heavy machinery, construction |
Our precision CNC machining services include expert threading for all metric and imperial specifications.