Cycling Power to Calories Calculator
Turn your average power and ride time into calories burned and total work done.
How to use the power to calories calculator
- Enter your average power in watts.
- Enter the ride duration.
- Click Calculate to see kilojoules and calories.
The most accurate calorie estimate
If you ride with a power meter, kilojoules are the gold standard for energy expenditure — far more accurate than speed- or heart-rate-based estimates.
Frequently asked questions
How do you convert watts to calories?
Multiply average watts by ride time in seconds to get joules, then divide by 1000 for kilojoules. For cycling, kilojoules of work approximately equal calories burned.
Why do kJ and kcal match for cycling?
The human body is about 24% efficient, and the unit conversion between kJ and kcal happens to offset that, so 1 kJ of mechanical work ≈ 1 kcal expended.
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