Intermediate

Torque Calculator

Compute rotational torque (the turning effect of a force) from the lever arm, applied force and the angle between them.

m

Distance from pivot to force

N

deg

Between lever and force (90° = perpendicular)

N·m

Leave one of τ, r, F blank to solve for it
Torque (τ)
50N·m

τ = r · F · sin θ

rFLever arm r and applied force F at angle θ — τ = r · F · sin θ
Torque
50 N·m
Lever arm
0.5 m
Force
100 N
Angle
90 °
sin θ
1
Step by step
  1. 1

    sin θ

    sin(90°) = 1
  2. 2

    Torque τ = r × F × sin θ

    0.5 × 100 × 1 = 50
Results are estimates for general information only and are not professional advice — always verify important results independently before relying on them. Read the full disclaimer.
Quick answer

How does this calculator work?

Torque equals the lever arm times the force times the sine of the angle between them: τ = r·F·sin θ, measured in newton-metres. A force applied perpendicular (90°) gives maximum torque, while a force aligned with the arm gives none. Enter any two of τ, r, and F to solve for the third.

Formula
τ = r × F × sin(θ)
How this is calculated

Torque (τ) measures how strongly a force tends to rotate an object about a pivot. It is the product of the lever arm r (the distance in metres from the axis of rotation to the point where the force is applied), the force F in newtons, and the sine of the angle θ between the lever arm and the force direction. The result is expressed in newton-metres (N·m).

When the force is applied perpendicular to the lever arm (θ = 90°), sin θ = 1 and torque is maximised at τ = r·F. As the angle approaches 0° or 180°, the force points along the arm, sin θ approaches 0, and the torque vanishes because no rotation is produced. This calculator lets you leave any one of τ, r, or F blank and solves for it: F = τ / (r·sin θ) and r = τ / (F·sin θ).

Assumptions: the force is treated as a single point load and the lever arm is rigid. Division-by-zero cases (for example solving for force when r·sin θ = 0) are guarded and return no result. Angles are entered in degrees and converted internally to radians.

Frequently asked questions

Force is a linear push or pull measured in newtons, while torque is the rotational equivalent measured in newton-metres. Torque depends on both the force and the perpendicular distance from the pivot, so a small force at a long lever arm can produce a large torque.

Only the component of force perpendicular to the lever arm produces rotation. The sin θ term extracts that component, so torque is greatest at 90° and zero when the force is parallel to the arm.

The SI unit is the newton-metre (N·m). It is dimensionally the same as the joule but is kept distinct because torque is a rotational quantity, not an energy.

Also known as

torque
moment of force
lever arm
rotational force
find torque
tau=rf
moment calculator

APA

TG we-Calculate Editorial Team. (2026). Torque Calculator [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/torque-calculator

Chicago

TG we-Calculate Editorial Team. "Torque Calculator." TG we-Calculate. 2026. https://we-calculate.com/calculator/torque-calculator.

IEEE

TG we-Calculate Editorial Team, "Torque Calculator," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/torque-calculator

BibTeX

@misc{wecalculate_torque_calculator, title = {Torque Calculator}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/torque-calculator}}, year = {2026}, note = {TG we-Calculate} }

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