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Potential Energy Calculator

Calculate gravitational potential energy using PE = mgh. Enter mass, height, and gravity to get energy in joules instantly.

kg
m
m/s²
Examples

PE = 2 × 9.81 × 1.5 = 29.43 J

Potential Energy
29.43 J

Small stored energy — like a book on a low shelf. Measured above the chosen reference point (usually the ground).

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Examples

How It Works

Formula

PE=m⋅g⋅hPE = m \cdot g \cdot h

Variables

PEPE

Gravitational potential energy(J)

mm

Mass(kg)

gg

Gravitational acceleration(m/s²)

hh

Height above the reference point(m)

Enter the mass in kilograms, the height in metres, and optionally adjust the gravitational acceleration (defaults to Earth's 9.81 m/s²). The calculator computes PE = mgh and returns the result in joules.

Gravitational potential energy is the work a uniform gravitational field would do on an object as it moved from the reference height to its current position. For small heights compared to a planet's radius, the field is approximately constant, so PE = m·g·h. The calculator multiplies your three inputs and returns the energy stored relative to the reference point you choose.

Frequently Asked Questions

01What is gravitational potential energy?
Gravitational potential energy is the energy an object has due to its position in a gravitational field. It equals mass times gravitational acceleration times height: PE = mgh.
02What units does potential energy use?
Potential energy is measured in joules (J) when mass is in kilograms (kg), gravity in m/s², and height in metres (m).
03Why does the default gravity value show 9.81?
9.81 m/s² is the standard gravitational acceleration at Earth's surface. You can change it for other celestial bodies (e.g., 1.62 m/s² for the Moon, 3.71 m/s² for Mars).
04Can potential energy be negative?
Yes, if the height is negative (below the reference point). The reference level is arbitrary — what matters physically is the change in potential energy.
05How are kinetic and potential energy related?
In a conservative system, the total mechanical energy (KE + PE) is conserved. As an object falls, PE converts to KE. At the highest point, PE is maximum and KE is zero.

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