Pulleys Calculator

Calculate effort force, mechanical advantage, and work in pulley systems

MA = nE = L ÷ n

What is a Pulley?

A pulley is a wheel on an axle that redirects force. Multiple pulleys reduce the effort needed to lift a load.

Mechanical Advantage

The MA of a pulley system equals the number of rope segments supporting the load. More pulleys = greater MA.

The Trade-off

Reducing effort means pulling more rope. The total work done is always the same — energy is conserved.

Formula

Pulley system mechanics

MA = n  |  Effort = Load ÷ n

n — number of rope segments supporting the load

LLoad ForceN
nNo. of Pulleys—
EEffort ForceN

Enter Values

The weight or resistance force the pulley system must lift

N

Count of rope segments supporting the load (equals mechanical advantage)

pulleys

The length of rope you pull through the pulley system

m

More pulleys = less effort needed, but you must pull the rope a greater distance. The trade-off is always equal work.

No result yet

Enter the load, number of pulleys, and rope distance on the left, then press Calculate Pulleys to see your result.

Example Problems

Try these values to see how the calculator works

Single Fixed Pulley

Load200 N
Pulleys1
Rope Pulled5 m
Effort200 N
MA1

Double Movable Pulley

Load400 N
Pulleys2
Rope Pulled10 m
Effort200 N
MA2

Block & Tackle (4 pulleys)

Load800 N
Pulleys4
Rope Pulled16 m
Effort200 N
MA4