Free activity calculator
Calories burned calculator
Estimate exercise calories from activity MET value, body weight, and duration with transparent assumptions.
Reviewed February 12, 2026
MET-based estimate
Estimated calories
304 kcal
Estimated hourly rate
405 kcal/h
This is a broad activity estimate, not a measurement of your individual energy expenditure.
What this result means
Choose an activity, body weight, and duration to estimate exercise energy expenditure using a MET-based formula. The result is a broad estimate; individual efficiency, intensity, conditions, and measurement error can change actual expenditure.
Calories = MET × 3.5 × body weight in kg ÷ 200 × minutes.
What a MET estimate means
One MET represents a standardized resting energy cost. An activity assigned 8 METs is estimated at eight times that resting reference.
The activity values in this tool are broad examples based on the Adult Compendium of Physical Activities. Your exact intensity may not match the category.
Do not treat calories as exact
Wearables and calculators can produce different answers because they use different models and inputs. Use the same method for rough comparisons rather than compensating for every estimated calorie with food.
LogFast is a workout product, not a nutrition prescription tool. For medical or nutrition guidance, work with an appropriately qualified professional.
Frequently asked questions
How are workout calories calculated?
This tool uses activity MET value, body weight, and duration in a standard estimation formula.
Are smartwatch calories accurate?
They are estimates and can vary by device, activity, intensity, and individual physiology.
Does strength training burn calories?
Yes. The amount varies widely with exercise selection, rest periods, load, duration, and body size.
Sources and assumptions
Track the work, not a perfect calorie claim
Keep the activity that produced the estimate.
LogFast records the actual sport, run, lift, or class with duration and effort so your history stays useful even when calorie estimates are broad.
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