Potential Energy Calculator
Work out gravitational potential energy from mass and height, or rearrange to solve for either one.
Fill in two of mass, height, and energy (gravity is set for Earth by default) — the calculator solves for the blank using PE = m·g·h.
Potential energy
196.2J
Mass
2kg
Height
10m
Gravity defaults to 9.81 m/s² for Earth. Swap in 1.62 for the Moon or 3.71 for Mars if you want a different world.
How it works
Gravitational potential energy is the energy an object has stored up by sitting at some height. Lift a 2 kg book 10 meters up and you've given it about 196 joules — energy that turns back into motion the moment it falls.
The formula is mass times gravity times height, PE = m·g·h. Gravity is set to 9.81 m/s² for Earth, but you can drop in 1.62 for the Moon or 3.71 for Mars and see how much less it takes to store the same lift somewhere with weaker gravity.
Fill in any two of mass, height, and energy and leave the last one blank to solve for it. That's handy for questions like how high you'd have to lift a given mass to bank a certain amount of energy, or how heavy something must be to hold a known amount at a fixed height.
Frequently asked questions
What's the reference point for height?
Potential energy is always measured relative to some baseline you choose — usually the ground or a tabletop. The number tells you the energy relative to that zero level, so pick whatever height counts as 'the bottom' for your problem.
Why does gravity default to 9.81?
That's Earth's average surface gravity in m/s². It varies a hair with latitude and altitude, but 9.81 is close enough for nearly every everyday calculation. Change it in the box for other planets.
How is this different from kinetic energy?
Potential energy is stored by position, kinetic energy is carried by motion. As something falls, potential energy converts into kinetic energy while the total stays the same, which is why a dropped object speeds up.