Science

Kinetic energy calculator

Mass and velocity → kinetic energy (½ m v²) in joules.

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  • Free
  • Private (processed locally)
  • No sign-up

ℹ️ E = ½ × m × v². Result in joules. For km/h → m/s, divide by 3.6. 100% local.

Calculate kinetic energy

Enter the mass (kg) and velocity (m/s). The tool applies E = ½ m v² and gives the result in joules and kilojoules.

Key points

  • m in kg, v in m/s, E in joules
  • km/h → m/s: divide by 3.6
  • Speed ×2 → energy ×4
  • 1 kJ = 1000 J

Example

InputValue
Mass2 kg
Velocity3 m/s
Kinetic energy9 J
In kilojoules0.009 kJ

100% local calculation, no data sent.

Frequently asked questions

What is the formula?

E = ½ × m × v², with m in kg and v in m/s. The result is in joules.

Example calculation?

2 kg at 3 m/s → ½ × 2 × 3² = 9 J.

What if I have km/h?

Convert: speed in m/s = km/h ÷ 3.6. Then apply the formula.

Why velocity squared?

Energy grows with the square of speed: doubling speed quadruples the energy.