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MasterMath

Potential Energy Calculator

The energy stored by height: mass times gravity times how high something is. It converts straight into kinetic energy on the way down.

Result

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How this was worked out

    The formula

    Ep = m · g · h

    SymbolQuantityUnit
    EpPotential energyJ
    mMasskg
    hHeightm

    What it means

    Gravitational potential energy is the work done lifting something against gravity, and it is exactly what you get back when it falls. That equivalence is why the two formulas combine so neatly in free-fall problems.

    How to work it out by hand

    1. Multiply the mass by the acceleration due to gravity
    2. Multiply by the height
    3. The answer is in joules

    What is worth knowing

    Potential energy is always measured from a reference point you choose, and only differences in it have physical meaning — the floor, the ground and sea level are all valid zeros. That freedom is not a weakness: it reflects that what matters is the change, not the absolute value. Pumped-storage hydroelectricity is this formula at scale, pumping water uphill when power is cheap and letting it fall through turbines when demand peaks. It remains by far the largest form of grid storage in use.

    Frequently asked questions

    Where do I measure the height from?

    From whatever reference you choose. Only differences in potential energy have physical meaning, so the zero point is yours to pick.

    What happens to it when the object falls?

    It converts into kinetic energy. Ignoring air resistance, the total of the two stays constant.

    Is potential energy stored in the object?

    Strictly it is stored in the object–Earth system, not in the object alone. It takes both to have a gravitational field.

    How is this used in practice?

    Pumped-storage hydroelectricity is exactly this: water lifted when power is cheap, released through turbines when demand peaks.