Levers Calculator

Calculate effort force and mechanical advantage for all three lever classes

MA = EA ÷ LAE = L ÷ MA

Class 1 Lever

Fulcrum between effort and load. Can have MA > 1 or < 1. Examples: seesaw, crowbar, scissors.

Class 2 Lever

Load between fulcrum and effort. Always MA > 1 — always a force multiplier. Examples: wheelbarrow, nutcracker.

Class 3 Lever

Effort between fulcrum and load. Always MA < 1 — trades force for speed/range. Examples: tweezers, forearm.

Formula

Lever principle of moments

Load × Load Arm = Effort × Effort Arm

MA = Effort Arm ÷ Load Arm

LALoad Armm
EAEffort Armm
LLoad ForceN
EEffort ForceN

Enter Values

Seesaw, scissors, crowbar

The resistance force or weight being moved by the lever

N

Distance from the fulcrum to where the load is applied

m

Distance from the fulcrum to where effort is applied

m

A longer effort arm gives greater mechanical advantage. Class 1 and 2 levers can have MA > 1; Class 3 levers always have MA < 1 but provide speed/range advantage.

No result yet

Select a lever class, enter the load and arm lengths on the left, then press Calculate Lever to see your result.

Example Problems

Try these values to see how the calculator works

Crowbar (Class 1)

Load600 N
Load Arm0.2 m
Effort Arm1.2 m
Effort100 N
MA6

Wheelbarrow (Class 2)

Load400 N
Load Arm0.5 m
Effort Arm1.5 m
Effort133 N
MA3

Tweezers (Class 3)

Load10 N
Load Arm0.08 m
Effort Arm0.04 m
Effort20 N
MA0.5