Kinetic Energy Calculator (KE = ½mv²)
A free kinetic energy calculator that finds KE = ½ × m × v² instantly. Enter mass in kilograms and velocity in meters per second to get the result in joules. Ideal for physics homework, lab work, and engineering checks.
Enter a mass and velocity to see the kinetic energy.
How it works
What is kinetic energy?
Kinetic energy is the energy an object has because of its motion. It depends on the object's mass and on the square of its speed, so velocity has a far greater effect than mass.
The standard unit is the joule (J), where 1 J = 1 kg·m²/s². Doubling the speed multiplies the kinetic energy by four.
The kinetic energy formula
Kinetic energy is calculated with KE = ½ × m × v², where m is mass in kilograms and v is velocity in meters per second.
This calculator squares the velocity, multiplies by the mass, then halves the result, returning the answer in joules.
Frequently asked questions
›What units does this calculator use?
Mass is entered in kilograms (kg) and velocity in meters per second (m/s); the result is in joules (J).
›What is the kinetic energy formula?
Kinetic energy equals ½ × mass × velocity squared, written KE = ½mv².
›Why does velocity matter more than mass?
Velocity is squared in the formula, so doubling the speed quadruples the kinetic energy, while doubling the mass only doubles it.
›Can I calculate KE for any moving object?
Yes. The formula applies to any object with mass moving at non-relativistic speeds, from a ball to a car.
›How do I convert joules to other units?
1 joule equals about 0.239 calories or 0.000278 watt-hours; multiply the joule result by the appropriate factor.
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