How to use it
- Enter speed and its unit.
- Enter an assumed reaction time and deceleration value.
- Calculate the simplified distances for educational comparison only.
Braking Distance Calculator
Explore a simplified physics estimate of reaction and braking distance.
Important: This is an educational estimate only and must not be used for driving safety decisions. Actual stopping distance varies with the vehicle, tires, brakes, road, weather, driver and other conditions. Follow applicable rules and qualified professional guidance.
About the Braking Distance Calculator
This educational physics model separates distance traveled during a chosen reaction time from idealized braking distance.
Formula
Reaction distance equals speed in m/s × reaction time. Braking distance equals speed² ÷ (2 × deceleration).
Example
At 100 km/h with 1.5 seconds reaction time and 7 m/s² deceleration, the simplified total is about 96.8 meters.
Critical limitation
The model omits many real conditions and must never guide driving or braking decisions. It is not a test of vehicle safety or legal compliance.