Work and Power Calculator
Calculate mechanical work from force and distance, and the power it takes.
Please note: Results use idealised models — point masses, no air resistance, ideal gases and uniform materials. Real experiments deviate. Use these for study and estimation, not for engineering sign-off.
What the Work and Power Calculator does
Work is force applied through a distance, counting only the component of the force that points along the motion. Power is how quickly that work is done. The distinction matters: lifting a load up a staircase is the same work however fast you climb, but running it takes far more power.
Formula
W = F × d × cos(θ)P = W ÷ tInput energy = W ÷ efficiency1 hp = 745.7 W
Inputs explained
| Input | Unit | Required | Notes |
|---|---|---|---|
| Force applied | number | Yes | — |
| Force applied unit | one of 5 options | Yes | — |
| Distance moved | number | Yes | — |
| Distance moved unit | one of 9 options | Yes | — |
| Angle between force and motion | ° | Optional | Zero when you push in the direction of travel. 90° does no work at all. Accepts 0 or more, up to 180. |
| Time taken | number | Optional | Leave blank to skip the power calculation. |
| Time taken unit | one of 6 options | Yes | — |
| Machine efficiency | % | Optional | Accepts 0 or more, up to 100. |
How to use it
- Choose Force applied unit and Distance moved unit.
- Enter Force applied and Distance moved.
- Optionally add Angle between force and motion, Time taken and Machine efficiency.
- Select Calculate.
Worked example
Pushing a crate with 500 N over 10 m in 20 seconds, force aligned with the motion.
- Force
- 500 N
- Distance
- 10 m
- Angle
- 0°
- Time
- 20 s
W = 500 × 10 × cos(0°) = 5,000 J. Power = 5,000 ÷ 20 = 250 W, about 0.335 hp.
Frequently asked questions
Why does the angle matter?
Only the part of the force pointing along the motion contributes. Pulling a sled by a rope at 60° means just half the force does any work.
How much power can a person produce?
Around 75 W sustained, 300 W for a fit cyclist over an hour, and over 1,000 W in a brief sprint.