Torque Calculator
Calculate torque from applied force, lever arm length and angle.
Assumptions used in this calculation
- Rigid lever arm: Assumes a rigid, massless lever arm and a force applied at a single point at the end of it.
About this calculator
Anyone using a wrench, a lever, or a door handle is applying rotational force, but judging by feel whether a given push will actually loosen a stubborn bolt or swing a heavy door means accounting for both how hard you push and where and at what angle you push it, not just the raw force. This calculator computes torque, the rotational analogue of force, from the applied force, the lever arm length (distance from the pivot to where the force is applied), and the angle between the force direction and the lever arm, using τ = F × r × sin(θ). The sine term matters because only the force component perpendicular to the lever arm contributes to rotation, a force applied along the arm's length produces no torque at all. Getting torque right by hand means correctly applying that trigonometric relationship rather than just multiplying force by distance, a common shortcut that only works at exactly 90°. This is the same formula behind torque wrench specs and mechanical engineering calculations.
Worked example
20N force, 0.5m lever arm, 90° angle
Result: 10 N·m
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