Calculate
How to use this calculator
Choose the formula (if there is more than one), choose what you want to find, then fill in the other values using the units shown. The calculator rearranges the formula, puts your numbers in, and shows every step.
How it's calculated
Mechanical advantage MA = load ÷ effort. Velocity ratio VR = distance moved by effort ÷ distance moved by load. Efficiency = (MA ÷ VR) × 100.
Worked example
A machine lifts a 400 N load with a 100 N effort (MA = 4). If VR = 5, efficiency = (4 ÷ 5) × 100 = 80%.
Frequently asked questions
Why is efficiency less than 100%?
Friction and the weight of moving parts waste some energy.
Examples of simple machines?
Levers, pulleys, inclined planes, wheel and axle, and gears.
Related tools
Last updated October 2026. Results are for learning and guidance; always check important work. Calculations run in your browser and are not stored.