Cycling outdoors depends on speed, wind and hills, so speed bands are only a rough guide. Indoors, power in watts is a direct measure of the work you are doing, which makes stationary bike estimates more reliable when your bike shows it.
Stationary bike vs outdoor riding
At the same effort, the two are close. Outdoor rides often include coasting, stops and downhills, which lower the average. Indoor rides tend to be steady, so a 45 minute stationary session can burn as much as a longer outdoor ride. Spin classes are rated about 9 METs on average, but they vary widely by instructor and how hard you push.
Using watts for a better estimate
If your bike or trainer shows watts, use your average for the session. Peloton, Zwift and most smart trainers show it. A moderate ride for most people sits around 100 to 150 watts. Without a power reading, choose by speed or effort and treat the result as a rough estimate.
Total vs net calories
Your body burns calories all day just to keep running, roughly 1 MET. The total figure includes those calories. The net figure subtracts them, leaving only the extra energy the activity cost. Net is the more honest number if you are thinking about how much a workout adds to a calorie deficit.
Don't count the same calories twice
If you set a calorie target with our TDEE calculator and chose an activity level that includes your usual workouts, those workouts are already in your target. Adding exercise calories on top would count them twice. Use these numbers for workouts beyond your normal routine, or to compare activities.
How accurate is this?
MET values are averages measured in groups of adults aged 19 to 59. Your real burn can differ by 10 to 20% or more because of fitness, technique, body composition and how hard you actually worked. Adults over 60 often burn somewhat less than these estimates; a separate Compendium for older adults exists for that reason. Treat the result as a solid estimate rather than an exact count. Fitness trackers are no more precise; see how accurate fitness trackers are for calories.
Questions people ask
How many calories does 30 minutes on a stationary bike burn?
At a general effort, about 250 calories in total for a 155 lb person. At 126 to 150 watts it is closer to 295. Heavier riders burn more.
Does an e-bike still burn calories?
Yes, though less than a regular bike. Riding with light motor support is rated about 6 METs, close to moderate walking uphill. High support drops it to about 4 METs.
Is cycling good for weight loss?
Cycling is easy on the joints and easy to do for a long time, which helps it add up. Like any exercise, its main role in weight loss is supporting a modest calorie deficit and preserving fitness.
Sources
- Herrmann SD, Willis EA, Ainsworth BE, et al. 2024 Adult Compendium of Physical Activities: a third update of the energy costs of human activities. Journal of Sport and Health Science. 2024;13(1):6–12. pacompendium.com