A mini stair stepper takes up little space and allows you to exercise indoors at any time of day. The calories that you burn while using your stair stepper depend primarily on your weight.
A 120-lb. exerciser burns about 350 calories per hour on a mini stair stepper, according to the Weight/Fat Loss website. To burn the same amount while walking 4 mph, you would need to walk for additional 15 minutes.
A 150-lb. person burns an additional 80 calories per hour, making their hourly total on the stair stepper 430 calories. You can burn about the same amount by mountain biking for 48 minutes.
A 200-lb. exerciser burns about 560 calories per hour on the mini stair stepper. Burn the same amount of calories by swimming at a moderate pace for 8 additional minutes.