Bolt Thread Lengths FMW Fasteners
Standard Thread Length for Bolts Inch Imperial Bolt Diameter 6 quot and Shorter Longer Than 6 quot A325 Thread Length 1 4 0 75 1 5 16 0 875 1 125 3 8 1 1 25 7 16 1 125 1 375 1 2 1 25 1 5 1 9 16 1 375 1 625 5 8 1 5 1 75 1 25 3 4 1 75 2 1 375 7 8 2 2 25 1 5 1 2 25 2 5 1 75 1 1 8 2 5 2 75 2 1 1 4 2 75 3 2 1 3 8 3 3