Boneyard Tools

Cycling Calories Calculator

Enter your average power in watts and ride duration in minutes to estimate the work done in kilojoules and the calories you burned.

How to calculate cycling calories

  1. Enter your average power in watts from a power meter or trainer.
  2. Enter the ride duration in minutes.
  3. Read the mechanical work in kilojoules and estimated calories burned.

Examples

Two hours at 200 watts

average power 200 W, duration 120 min
1440 kJ, about 1434 calories

One hour at 250 watts

average power 250 W, duration 60 min
900 kJ, about 896 calories

Frequently asked questions

How are cycling calories calculated from power?

Work in kilojoules equals average power times seconds divided by 1000. Divide that by metabolic efficiency and by 4.184 to convert kilojoules to calories.

Why do kilojoules and calories come out so close?

Human pedalling is roughly 24 percent efficient. Dividing kilojoules by 0.24 and by 4.184 gives a factor near one, so burned calories nearly match the kilojoules.

What efficiency should I use?

A value around 0.20 to 0.25 is typical, with 0.24 as a common default. Trained riders sit near the top of that range, so a higher efficiency lowers the calorie estimate.

Is this more accurate than heart rate estimates?

Yes, when you have a power meter. Direct power measurement of work done is far more reliable than calorie estimates based on heart rate or speed alone.

Does this include resting metabolism?

No. It estimates only the energy used to ride. Your body also burns baseline calories at rest, which this active estimate does not add on top.

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