Bolt Torque Calculator

Bolt Torque & Preload Calculator

Calculate tightening torque and resulting clamp force for metric and imperial bolts.

T = K × F × d   (Nm)
K = Nut factor: 0.20 plain, 0.15 zinc+oil, 0.10 PTFE
F_target = 0.75 × σ_y × A_s   (reusable)