Stopping (Braking) Distance Calculator

Common questions that arise in traffic accident reconstructions are "What was the vehicle's initial speed given a skid length?" and "What distance is required to stop from this speed?". You will be able to answer these questions by simply entering the road surface type, units, and speed or distance below.

Pick Metric or Imperial, and chose a friction surface. The stopping distance or skid length with be displayed after you press the "Calculate" button.


Select units:

Choose your road condition:

Initial Speed Calculator
Enter skid length:

Stopping Distance Calculator
Enter speed:


This result is a rough approximation for your information. Road conditions depend on a number of factors such as slope, wear rate and depth of snow or ice on the roadway. Also, this formula does not take into account any speed loss due to collision forces, or the time required to perceive and then respond to a given situation.

To discuss the above calculations, and any variables that might affect your specific case, please contact one of our forensic engineers.