How calories burned is estimated

This calculator uses MET values, a standardised measure of exercise intensity where one MET is the energy you use sitting quietly. An activity rated at 8 METs costs roughly eight times that. Multiplying METs by bodyweight and duration gives a reasonable population-level estimate of energy cost.

Individual results vary widely. Fitness level, movement efficiency, terrain, temperature and how hard you actually work all shift the real number, and fitness trackers routinely overestimate by 20 percent or more, particularly for weight training.

The most useful thing this figure does is put exercise in perspective. A 45 minute run burns roughly what a large muffin and a coffee contain. Exercise is excellent for health, strength and appetite regulation; it is a slow and unreliable way to create a calorie deficit on its own.

How MET values work

One MET is the energy cost of sitting quietly, roughly 3.5 millilitres of oxygen per kilogram of bodyweight per minute. An activity rated at 10 METs costs about ten times that. MET values come from published compendiums of physical activity and describe population averages, not your specific physiology.

MET values for common activities

Why the number is smaller than you hoped

A 45 minute run at a decent pace burns roughly 600 kcal for an 80 kg person, which is a large muffin and a latte. This is not an argument against exercising; it is an argument against treating exercise as your primary tool for creating a calorie deficit. Diet moves the deficit; training decides what kind of tissue you keep and does a great deal for your health that has nothing to do with calories.

Common overestimates

Using this number correctly

• Do not add it to a TDEE that already includes your training. If you selected an active multiplier, the training is already counted once.
• Do not eat it back in full. Given the error margins, replacing every burned calorie often erases the deficit entirely.
• Use it for comparison, not accounting. It is genuinely useful for deciding whether a session is worth the time you have.
• Remember the after-effects are small. Post-exercise elevated metabolism is real but typically adds only a modest amount to the session total.
• Weight training pays off indirectly. Fewer calories per session, but preserved muscle keeps your resting burn higher over months.

Frequently asked questions

More tools: all calculators · Full Plan · Recomp · Body fat · Macros · Cheapest whey per 20 g

General information, not medical advice. Consult a qualified professional before changing your diet, especially with a medical condition.