Work out reaction distance instantly with clear inputs, formula shown and shareable results.
Reaction distance is speed times reaction time, entirely linear. At 100 km/h the car travels 27.8 m every second, so an extra half second of distraction adds nearly 14 m — more than three car lengths before the brakes are even applied.
Reaction distance
d = v x total reaction time, with v in m/s
0.7-1.0 seconds for an alert driver expecting a hazard, 1.5 seconds or more when surprised. Highway design typically assumes 2.5 seconds.
Texting adds one to three seconds of eyes-off-road time, which at motorway speed is 30-80 m travelled effectively blind.