Automotive heat
Brake Energy & Heating Calculator
Braking removes kinetic energy from a moving vehicle. In friction braking, much of that energy ultimately becomes thermal energy in rotors, drums, pads, tyres, air and surrounding components. This calculator shows the scale of that energy and an idealised temperature rise for a selected brake mass.
Estimate braking energy
Why a single stop can involve a large amount of energy
Kinetic energy grows with the square of speed. Doubling vehicle speed multiplies translational kinetic energy by four when mass stays the same. That is why high-speed braking can create a much larger thermal load than a similar stop from a lower speed.
Where the energy goes
In a friction-brake system, rotors or drums and pads receive much of the braking energy. Some energy also leaves through tyres, air drag, bearings and other losses. In hybrid and electric vehicles, regenerative braking can send part of the vehicle's kinetic energy back into the electrical system instead of dissipating all of it as frictional heat.
Why real brake temperatures need a transient model
Actual rotor and pad temperatures depend on front-to-rear brake balance, component mass, geometry, airflow, repeated stops, thermal conductivity, radiation, contact conditions and temperature-dependent material properties. The simple temperature rise here shows an energy scale rather than predicting a real component temperature.
Related reading
Explore heat in vehicles, read about frictional heating, or estimate heat from a specified friction force and sliding speed.