The Speed Calculator finds speed, distance or time from the other two, in many units.
Speed = 36 km/h
| Speed | 10 m/s |
| 36 km/h | |
| 22.369363 mph | |
| 19.438462 knots |
Speed = distance ÷ time; distance = speed × time; time = distance ÷ speed. These three formulas solve most travel problems.
Worked example (defaults): 100 m in 10 s is 10 m/s, which is 36 km/h or about 22.4 mph.
1 m/s = 3.6 km/h ≈ 2.237 mph. 1 knot = 1 nautical mile per hour = 1.852 km/h. The speed of sound is about 343 m/s; light is 299,792,458 m/s.
Average speed is total distance divided by total time, not the average of speeds. Driving 60 miles at 30 mph and 60 miles at 60 mph averages 40 mph, not 45.
What is velocity? Speed with a direction.
How fast is a typical walk? About 5 km/h (3 mph).
How do I enter hours and minutes? Use decimal hours or choose minutes.