Total Stopping Distance: Reaction Distance Plus Braking Distance
Last reviewed: 2026 · Driviology Road Safety Education Team
Quick Answer
Total stopping distance is reaction distance - how far the vehicle travels before the driver even begins braking - plus braking distance itself, and both parts increase with speed.
Our guide to braking distance notes that it is only part of the total picture; this page covers the full calculation.
Reaction Distance Comes First
Before the brakes are even applied, the vehicle continues travelling for the length of the driver’s reaction time, which itself grows with speed.
Then Braking Distance
Only after reaction distance does the vehicle begin the braking phase covered in our dedicated guide to factors affecting braking distance.
Why the Combined Total Matters
Judging safe following distance based on braking distance alone underestimates how far a vehicle actually travels before coming to a complete stop.