Driving Formulas

Key distance formulas for the German driving theory exam

Formula Reference

Reaction Distance

(speed / 10) x 3 meters

Braking Distance (normal)

(speed / 10)² meters

Braking Distance (emergency)

(speed / 10)² / 2 meters

Stopping Distance

reaction distance + braking distance

Following Distance

speed / 2 meters

Wet Road

braking distance x 2

Interactive Calculator

50 km/h
30 km/h200 km/h

Reaction

15.0 m

Braking

25.0 m

Stopping

40.0 m

Following

25.0 m

Distance Comparison at 50 km/h

Reaction Distance15.0 m
15m
Braking Distance25.0 m
25m
Total Stopping Distance40.0 m
40m
Safe Following Distance25.0 m
25m

Practice Problems

1You are driving at 100 km/h on a dry road. What is your total stopping distance with normal braking?

2At 50 km/h on a wet road, what is your braking distance with emergency braking?

3What is the safe following distance at 80 km/h?

4You are driving at 120 km/h and perform emergency braking on a dry road. How far do you travel before stopping completely?

5Compare the stopping distances at 50 km/h and 100 km/h (normal braking, dry road). How much longer is it at 100 km/h?