Exercise Fat Burn Estimator
See how much body fat your workout burns — in grams, not just calories. Pick your activity or paste data straight from your fitness watch.
Body Fat Burned
grams of body fat
Total Calories
— kcal
Protein Burned
— g
Glycogen Burned
— g
Why grams of fat instead of calories?
Fat-adapted athletes and carnivore dieters burn a higher proportion of fat during exercise. The fat oxidation ratio varies by intensity, based on the respiratory exchange ratio (RER) from exercise physiology research:
- Low intensity (MET < 5): ~65% of energy from fat — walking, yoga, elliptical
- Moderate (MET 5–8): ~50% from fat — cycling, weightlifting, swimming
- High intensity (MET > 8): ~35% from fat — running, HIIT, jump rope
MET (Metabolic Equivalent of Task) values from the Compendium of Physical Activities (2024). 1g of fat = 9 kcal. 1g of protein = 4 kcal. 1g of glycogen = 4 kcal.
Fat-adapted carnivore dieters may burn an even higher percentage of fat at moderate intensity compared to carbohydrate-fueled athletes.
These are estimates. Actual fat oxidation depends on your metabolic state, training history, and whether you are fat-adapted.
Estimates based on MET values from the Compendium of Physical Activities (2024). Fat oxidation ratios derived from exercise physiology research on respiratory exchange ratios. Educational and informational purposes only — not medical or nutritional advice. Consult your healthcare provider before making dietary changes.