Bolt Thread Length
How to Calculate a Bolt Thread Length
At Arun Fasteners we are often asked about the thread length on differing size Hex Head Bolts. Below is a helpful guide.
NOTE: It is measured from UNDER the head
Bolt Thread Length
| 0 to 125mm | 2 x Diameter + 6mm |
| 125 to 200mm | 2 x Diameter + 12mm |
| 200+mm | 2 x Diameter + 25mm |
We’ve listed below a range of bolt sizes as an example:
| Bolt Size | Thread Length |
|---|---|
| M8 x 70 | 22mm |
| M10 x 180 | 24mm |
| M12 x 200 | 49mm |
| M14 x 280 | 53mm |
| M16 x 190 | 44mm |
| M18 x 300 | 61mm |
| M20 x 140 | 65mm |
| M22 x 360 | 69mm |
| M24 x 100 | 54mm |
Here are some examples of some Bolts we stock-
