Ground speed is very easy to calculate, once you have all the variables presented. Ground speed is typically measured for cars, planes and other vehicles. In order to calculate ground speed, you have to monitor how far the vehicle goes over a given period of time. For example, if you are in a car, you need to know how long it took you to get from point A to point B, then use that time to calculate your ground speed. For vehicles, ground speed is typically measured in miles per hour.
Things You'll Need
 Watch
 Calculator
 Map
 Ruler

Time how long it took you to get from one point to another. For example, you flew on a plane and it took you two hours to get from one point to another.

Look up the distance between the two points on a map by measuring with a ruler. Consult the map key to find the true distance between the points. For example, you flew on a plane, and the distance you flew is measured as 10 inches on the map, and each inch on the map represents 100 miles. The real distance you flew is 1,000 miles (10 x 100).

Convert the number to miles per hour to get the ground speed. In the example above, since you went 1,000 miles in 2 hours, the ground speed of the plane is 500 miles per hour (1,000/2 = 500).
References
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