Potential Energy Calculator
From a mass and a height, get the gravitational potential energy stored at that height — the energy waiting to be released as motion.
Mass and height, one number
Enter the mass in kilograms and the height in metres and the calculator returns the potential energy in joules (PE = m × g × h).
Standard gravity is built in
The calculator uses standard gravity g = 9.80665 m/s²; the true local value changes a little with latitude and altitude.
What is potential energy?
Stored energy of height
Gravitational potential energy is the energy an object stores simply because of how high it sits above a reference level. Lift something against gravity and you put energy into it; that energy is released as motion the moment it falls. It depends on just three things — the object's mass, the height it has been raised, and the strength of gravity — which makes it the single input physics students, engineers, and anyone sizing a hydro or lifting problem reach for first.
Enter a mass in kilograms and a height in metres to get the stored energy in joules instantly.
One short formula, built from the mass, the height, and standard gravity g (9.80665 m/s²).
PE = m × g × hMultiply the mass m (in kilograms) by standard gravity g (9.80665 m/s²) and by the height h (in metres), and the result comes out in joules — the SI unit of energy. The formula is linear in both mass and height, so doubling either one doubles the stored energy, and doubling both quadruples it.
Suppose you raise a 10 kg object to a height of 5 m.
Weight (mass × gravity)
10 × 9.80665 = 98.0665 — the gravitational force on the object, in newtons.
Multiply by height
98.0665 × 5 = 490.3325 — the force times the height it was raised.
Read the result
PE = 490.3325 J — the energy stored, ready to convert to motion if it falls.
The 490.3325 J figure is the energy locked into the object by its position. Drop it, and that potential energy converts almost entirely into kinetic energy — energy of motion — so the object reaches the ground carrying close to the same 490.3325 J, just in a different form. This is the principle behind hydroelectric power (water held behind a dam releases its potential energy through turbines), roller coasters (the long first climb stores the energy the whole ride spends), pendulums (energy sloshing between height and speed), and any lifting or crane calculation. Because the relationship is linear, the intuition is simple: lift twice the mass, or lift to twice the height, and you store twice the energy. That is why a heavier load on a tall shelf is worth respecting — it is holding more energy than a light object at the same height, and all of it is released if it falls.
The formula is exact for everyday situations, but a couple of practical points are worth keeping in mind.
Standard gravity and modest heights
This calculator uses standard gravity g = 9.80665 m/s², a fixed reference. The real value varies slightly with latitude and altitude, and PE = m × g × h assumes g stays constant — true only for heights small compared with the Earth's radius, not for satellites or spaceflight. The result is the energy relative to the reference level you chose for the height, so measure the height to the surface the object would actually fall to.