Everyday Life
Car Trip Time Calculator
Divide distance by your realistic average speed — not the speed limit — to get a driving time you can plan around.
Formula
Time (hours) = distance / average speed.
How it works
Average speed is almost always lower than the speed limit because of towns, traffic and junctions. Using 80% of the motorway limit is a realistic starting point.
For trips over two hours, plan a break every couple of hours — tired driving is slower and far less safe.
FAQs
Why is my trip always longer than the estimate?
Because average speed includes slowing for towns and traffic, which the speed limit alone ignores.
How much time should breaks add?
A good rule is 15 minutes every 2 hours of driving.
Does this include traffic?
Only if your average speed already accounts for it. For rush-hour trips, lower the average speed.