Kinetic Energy Calculator
Calculate the kinetic energy of a moving object from its mass and speed.
The energy of motion
Kinetic energy is the energy an object has because it is moving, and it depends on its mass and, crucially, the square of its speed. This calculates it from mass and velocity, a key quantity for understanding collisions, braking, and anything that moves.
Enter the mass and speed to see the kinetic energy.
Why speed matters so much
The single most important feature of kinetic energy is that it grows with the square of speed, not in proportion to it. Double the speed and the energy quadruples; triple it and the energy is nine times greater. This is why speed is so dangerous in a crash — a car at seventy carries far more than twice the energy it has at thirty-five, which must all be dissipated in a collision, and why stopping distances lengthen so dramatically with speed.
Kinetic Energy Calculator FAQ
Why is speed so important to kinetic energy?
Because energy grows with the square of speed — double the speed and the energy quadruples, which is why crashes at higher speeds are far more dangerous.
What does kinetic energy depend on?
The object's mass and the square of its speed — a heavier or faster object carries more energy of motion.
Is anything uploaded?
No. The calculation happens in your browser.