Kinetic energy calculator
Calculate the kinetic energy of a body from its mass and speed.
Kinetic energy
200,000 J
In kilojoules200 kJ
Use speed in m/s (divide km/h by 3.6).
How the calculation works
Kinetic energy is the energy of motion: KE = ½ · m · v², with mass in kg and speed in m/s. The result is in joules (J).
Frequently asked questions
Why is speed squared?
That's why doubling the speed quadruples the energy — and a crash's impact.
Related calculators
Updated on June 18, 2026 · by Rafael Rossi · Methodology & sources