How the conversion works
Distance is steps multiplied by stride length. Here, as in most pedometers and fitness apps, stride length means the distance covered by one step — from one heel strike to the next heel strike of the other foot. A mile is 160,934.4 cm, so with a 30-inch (76.2 cm) stride a mile is 2,112 steps and 10,000 steps is about 4.73 miles.
The height estimate
If you do not know your stride, the calculator can estimate it with a widely used rule of thumb: about 0.413 × height for women and 0.415 × height for men. A 170 cm woman gets an estimated stride of 70.2 cm; a 180 cm man, 74.7 cm. It is an average, not a measurement: leg length, walking speed, terrain and fatigue all change real strides, and running strides are much longer than walking ones. The page says when the estimate is in use.
Measuring your stride
Measuring beats estimating. Walk a known distance — 20 metres, or a running track lap — at your normal pace and count the steps, then divide the distance by the number of steps. Repeating it two or three times and averaging smooths out the first and last steps. Measure separately for walking and running if you do both.