| Stopping Time | Average Power |
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How Brakes Turn Motion Into Heat
A moving car carries kinetic energy, and brakes work by converting that energy into heat through friction. The rate of that conversion is power, and over a hard stop it can briefly reach numbers that rival or beat the engine. That is the surprising truth this tool shows: your brakes are, for a moment, the most powerful component on the car.
Average vs Peak Power
Average braking power is the total energy divided by the stopping time. Peak power is higher and happens at the start of the stop, when the car is moving fastest, because power equals force times speed. A firm stop from highway speed can peak at several hundred horsepower for a fraction of a second.
Heat, Fade, and Cooling
All that heat has to go somewhere. One stop is easily absorbed, but repeated hard stops on a mountain descent or race track stack heat faster than the brakes can shed it. As temperature climbs, pad friction drops and the fluid can boil, which is brake fade. Bigger rotors and better cooling exist to manage exactly this.
Frequently Asked Questions
Is this the same as engine brake horsepower?
No. Engine brake horsepower is power measured at the crankshaft on a dynamometer. This tool calculates the power your brakes dissipate while stopping. For engine output, use the Horsepower calculator.
Why is peak power so high?
Power is force times speed, so the same braking force produces the most power at the highest speed, right at the start of the stop.
Does this include air and rolling resistance?
No, it counts only the energy the brakes absorb. Aerodynamic drag and rolling resistance help slow the car too, so real brake load is slightly lower.