Wrenches, engines, and rotating machinery all run on torque = force × lever arm × sin(angle). Enter what you know and we'll solve the rest, step by step.
A torque calculator lets you instantly compute the rotational force produced when a force is applied at a distance from a pivot point, using the formula τ = rF sinθ. Enter the applied force, the lever arm distance, and the angle between them, and the calculator returns the resulting torque — letting you analyze rotational mechanics for physics problems, mechanical engineering, or everyday tool use.
Torque is the rotational equivalent of force in classical mechanics. Just as force causes objects to accelerate in a straight line, torque causes objects to accelerate rotationally around a pivot or axis. The key insight is that the same force applied farther from the pivot, or at a more perpendicular angle, produces more rotational effect — this is why a long wrench makes loosening a stubborn bolt far easier than a short one, and why pushing a door near its hinge barely moves it while pushing near the handle swings it open easily.
This calculator is useful in many contexts: physics students use it to solve rotational mechanics problems, mechanical engineers use it to size fasteners, gears, and drive shafts, automotive enthusiasts use it to understand engine specifications, and anyone using hand tools benefits from understanding why lever arm length matters so much for applying force efficiently.
A mechanic applies 50 N of force perpendicular to a 0.3-meter-long wrench to tighten a bolt. Using τ = rF sinθ: τ = 0.3 × 50 × sin(90°) = 0.3 × 50 × 1 = 15 N·m. This is the rotational force being applied to the bolt.
The torque value this calculator produces represents the rotational effect of the applied force around the specified pivot point — a larger value means a stronger tendency to cause rotation. When comparing your result to the reference table, notice how torque scales from small everyday tasks (a few newton-meters for a jar lid or door knob) to substantial mechanical forces (tens of newton-meters for wrenches, hundreds to thousands for engines) — reflecting both the force magnitudes and lever arm lengths involved. If your calculated torque seems unexpectedly low despite significant force, double-check your angle — a force applied nearly parallel to the lever arm (close to 0° or 180°) contributes very little rotational effect even if the force itself is large.
Enter the applied force, the lever arm (distance from the pivot point), and the angle between the force and the lever arm — the calculator computes torque using τ = rF sinθ.
| Scenario | Torque |
|---|---|
| Twisting open a stubborn jar lid | 2 N·m |
| Turning a door knob | 5 N·m |
| Tightening a bolt with a wrench | 40 N·m |
| Typical passenger car engine at peak | 300 N·m |
| Heavy-duty diesel truck engine at peak | 2,000 N·m |