Calories Burned Calculator Guide
A calories burned calculator estimates the energy cost of a workout from three inputs: what you did, how long you did it, and how much you weigh. Behind that simplicity sits a standardized method — MET values and the ACSM equation — worth understanding, because it tells you exactly how far to trust the number.
Open Calories Burned Calculator
The Method
Every activity in our calculator carries a MET value from the 2011 Compendium of Physical Activities (explained in the what are METs guide). The ACSM equation turns it into calories:
| Formula | kcal = MET × 3.5 × weight (kg) ÷ 200 × minutes |
|---|---|
| Example | Running 6 mph (9.8 MET), 70 kg, 30 min → 9.8 × 3.5 × 70 ÷ 200 × 30 ≈ 360 kcal |
Two properties follow directly. Burn scales linearly with body weight — an 85 kg runner burns ~21% more than a 70 kg runner at the same pace. And the number is gross: it includes the resting calories you would have burned anyway, which is the convention trackers use but slightly flatters the exercise.
Reading the Result Honestly
MET values are population averages measured under lab conditions. Your economy of movement, fitness level, and terrain shift the true number — 10–20% individual error is normal, which is also why your smartwatch disagrees. The estimate is excellent for comparing activities (is cycling or swimming the bigger burn for my hour?) and for tracking week-over-week trends; it is weak as a precise measurement of any single session.
Folding It Into a Calorie Plan
The common mistake is double counting: if your TDEE already uses an activity multiplier that reflects your training, the workout is already in your daily budget — eating it back adds it twice. Use per-session estimates to sanity-check which multiplier fits your real week, and pair intensity choices with the target heart rate calculator. For walking specifically — the most common query — the calories burned walking guide has ready-made tables by weight and speed.
Frequently Asked Questions
How accurate are calories burned calculators?
MET-based estimates are population averages — expect 10–20% error for an individual. They are most useful for
comparing activities and tracking trends, not as precise measurements.
Should I eat back the calories I burn exercising?
Usually not fully. Estimates are gross (they include resting burn) and tend to run high. If your TDEE already
includes an activity multiplier, eating exercise calories back double-counts them.
Which cardio burns the most calories?
Per minute, high-MET activities: jump rope (12.3 MET) and fast running (11.8 MET at 8 mph) top the common list.
Sustainable pace matters more than peak MET for total weekly burn.