Declan Connolly, PhD Responds:

Buying a pedometer can be sort of like buying a car. For a car, all you may need is something to get you from point A to point B, but there are lots of bells and whistles you can add on. For a pedometer, all you really need is something that will measure how many steps you take on your way from point A to point B.

A pedometer works by counting your steps and then multiplying your stride length to show you how far you have walked. This is the basic and most important function of a pedometer. When you’re shopping for one, be sure it’s sensitive enough to track each step you take but not so sensitive to measure foot jiggles when seated. For accuracy, you want to measure and count steps—so test it in the store before you make a purchase.

For a basic pedometer, expect to pay $10 to $20. Like luxury cars, the more advanced pedometers are more expensive—and may have better mechanisms that last longer. Some pedometers include heart rate monitors and calorie counters, but they go beyond the $20 price range. Pedometers also come with larger displays to allow easier reading as you walk.