Average Speed Calculator

speed = distance / time. Pick units and read average speed in mph or km/h.

Result

Loading calculator…

—

How to use this calculator

Enter distance and unit.
Enter total elapsed time including breaks.
Read mph and km/h.

About this calculator

Average speed is total distance divided by total time — including stops, traffic, and rest breaks. Different from "instantaneous speed" (what your speedometer reads). For a 3-hour drive covering 200 miles, average speed is 66.7 mph regardless of how fast you went at any moment.

Frequently asked

Should I include rest stops?+

For trip planning, yes — that's the realistic figure. For driving performance, only count time in motion.

How is this different from cruising speed?+

Cruising speed is what you held on the highway. Average speed includes traffic lights, ramps, slowdowns. On a typical highway trip, avg ≈ 0.85 × cruising.

Why is my GPS-displayed average lower than my speedometer reads?+

GPS averages over the whole trip including idle time. Speedometer shows instant speed. Both are accurate, just different measures.

How fast can a car average legally?+

On open highway with no stops, you can legally average ~70 mph in many US states. For a multi-day cross-country trip including rest stops, ~50-55 mph is more realistic.

Does this account for breaks?+

Yes — if you include break time in "total time", break time reduces average. The calculator doesn't add breaks for you.