Kinetic Energy Calculator
Energy of a moving object: KE = ½mv².
Quick answer
- Formula: KE = ½ × m × v²
- Worked example — Kinetic energy: 9.0000 J (full example below).
Kinetic Energy Calculator
| Kinetic energy | 9.0000 J |
| Kinetic energy | 0.00000250 kWh |
A 2 kg object moving at 3 m/s has exactly 9 J of kinetic energy.
Kinetic energy is the energy an object has because it is moving. It depends on the mass and, much more strongly, on the speed — doubling the speed quadruples the energy.
Enter mass in kilograms and velocity in metres per second. The result is in joules, with a kilowatt-hour equivalent for comparison with electricity units.
The formula
Worked example
A 2 kg object moving at 3 m/s has exactly 9 J of kinetic energy.
The example is pre-loaded in the result panel — press Calculate with your own numbers to replace it.
Frequently asked questions
Why does speed matter more than mass?
Velocity is squared in the formula. Doubling mass doubles KE, but doubling speed multiplies KE by four — which is why braking distances grow so quickly with speed.
How many joules are in a kilowatt-hour?
Exactly 3,600,000 J (1 kW for 3,600 seconds). Everyday kinetic energies are tiny fractions of a kWh.
Category: Science calculators
Sources & methodology
This calculator applies the formula shown on this page exactly as written, using the standard definitions for its inputs. Results are computed from the values you enter — no data is stored — and are rounded only for display.
Content last reviewed by CalcHub Editorial.
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