A pedometer senses your body motion and counts your footsteps. By knowing the length of your usual stride you can convert this count into distance. An accelerometer is a more advanced pedometer. It also shows your speed and distance.

In an accelerometer, a strain gauge allows the device to know how hard or soft each step is. Accelerometers are also known as piezoelectric pedometers. According to the latest research these have the most accurate and reliable step counting mechanism available.

Accelerometer-type step counters are more accurate for older adults and for overweight adults. The disadvantage of an accelerometer is a shorter battery life. The constant sampling of the strain gauge uses up the battery. Accelerometers also cost more than a regular pedometer.