Kinetic Energy Calculator
Calculate kinetic energy from an object's mass and velocity instantly with this free physics calculator in your browser.
Enter Values
How to use this calculator
- Enter mass (kg) and velocity (m/s).
- Read the kinetic energy in joules.
How it works
Kinetic energy = ½ × mass × velocity². Doubling the speed quadruples the energy.
Worked example
10 kg at 5 m/s. KE = ½ × 10 × 25 = 125 J.
Common mistakes
- Forgetting velocity is squared — speed matters far more than mass.
- Mixing units — use kilograms and metres per second for joules.
Frequently asked questions
How is kinetic energy calculated?
KE = ½ × mass × velocity². A 1,000 kg car at 20 m/s has ½ × 1000 × 400 = 200,000 J.
Why does speed matter more than mass?
Kinetic energy depends on velocity squared, so doubling speed quadruples the energy, while doubling mass only doubles it.
Why does speed matter so much?
Because velocity is squared: doubling speed multiplies kinetic energy by four.
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- Potential Energy Calculator
- Momentum Calculator
- Specific Heat Calculator
- Speed, Distance & Time Calculator
- Work Done Calculator
- Acceleration Calculator
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Cite this tool
Zerdly. (2026). Kinetic Energy Calculator. Retrieved from https://www.zerdly.com/tools/kinetic-energy-calculator/
Tip: Enter any known values to calculate the remaining results.
Designed to run locally in your browser. Tool inputs are not intentionally stored by Zerdly unless stated otherwise.