Search tools

Search for a command to run...

Force, Weight & Energy Calculator

Calculate force from mass and acceleration (F = ma), weight on Earth and other planets, kinetic energy and gravitational potential energy.

How to use

  1. 1Enter the mass and whichever of acceleration, velocity and height you need.
  2. 2Read the force, weight, kinetic and potential energy.

How it's calculated

F = m × a. Weight W = m × g (g = 9.80665 m/s² on Earth). KE = ½mv². PE = mgh.

Frequently asked questions

What's the difference between mass and weight?

Mass is how much matter an object has (kg); weight is the gravitational force on it (newtons), which changes from planet to planet.

What is a joule?

The SI unit of energy: 1 J is the work done by a 1 N force over 1 m.

Why does speed matter so much for kinetic energy?

KE grows with the square of speed — doubling speed quadruples the energy, which is why car crash severity rises sharply with speed.