Lever Calculator
Enter any three of effort force, effort arm, load force and load arm to balance a lever. The tool solves the fourth value from effort force times effort arm equals load force times load arm, then reports the mechanical advantage.
How to use the lever calculator
- Enter three of the four values: effort force, effort arm, load force, load arm.
- Leave the unknown box empty so the tool can solve for it.
- Read the missing value and the mechanical advantage of the lever.
Examples
Find the effort force
load = 200 N, load arm = 0.5 m, effort arm = 2 m
effort = 50 N, MA = 4
Find the load arm
effort = 50 N, effort arm = 2 m, load = 200 N
load arm = 0.5 m
Frequently asked questions
What is the law of the lever?
A lever balances when the effort force times its arm equals the load force times its arm: effort force x effort arm = load force x load arm. The arm is the distance from the fulcrum.
How do I find a lever's mechanical advantage?
Mechanical advantage equals the load force divided by the effort force, which is the same as the effort arm divided by the load arm. A longer effort arm gives more advantage.
What is the effort arm and load arm?
The effort arm is the distance from the fulcrum to where you push. The load arm is the distance from the fulcrum to the load. Both are measured along the lever.
How many values do I need to enter?
Enter exactly three of the four quantities. The tool rearranges the balance equation to solve for the one you leave blank.
What units should I use?
Use newtons for both forces and the same length unit, such as metres, for both arms. The mechanical advantage is a ratio, so its units cancel.
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