Why do different cycling calorie calculators give out different answers, often multiplication of one with a fixed number?

Question

I’m overweight and trying to lose weight via diet and stationary cycling but I’m confused with different calculators

if

Stationary bike says 100 calories (no weight input)

online calculators say 200 400 600 etc asking me the same info including weight

In: 4

Answer 1

Different cycling calorie calculators use different formulas to estimate the number of calories burned during a ride. Some factors that can affect the estimate include the cyclist’s weight, the intensity of the ride, and the duration of the ride.