Estimate resting metabolism
Your current body weight and body fat percentage provide a starting estimate of the calories your body burns at rest.
Free nutrition tool
Fat Loss Calculator From Calories Eaten and Burned
Estimate your resting metabolism from your body weight and body fat percentage, then add daily food intake and activity calories to see your estimated fat loss or gain per day, week, month, or chosen date.
Estimate your fat change
Estimate your resting metabolism from your body data, then compare it with your daily food intake and added activity calories.
Required body data
Your current body weight and body fat percentage estimate the calories your body burns at rest.
Daily calorie balance
166 kcal deficit
2,000 kcal eaten - 2,166 kcal burned1,666 kcal resting metabolism + 500 kcal additional
Per day
-0.02 kg
Estimated fat loss
Per week
-0.15 kg
Estimated fat loss
Per 30-day month
-0.65 kg
Estimated fat loss
Projection at a date
Choose a period and day to see the estimated change without a chart.
Projection period
Selected date
Choose a start date
Day 90
Based on the same daily calorie balance.
Fat change
-1.94 kg
Fat mass
18.06 kg
Body fat
23.14%
This uses an estimated resting metabolism from your body composition, not your complete daily energy expenditure. Include the movement and exercise you want to count in additional calories. Real changes can also differ because of water weight, lean mass, changing energy needs, and consistency.
Add your activity
Include walking, training, work, or other movement as additional calories burned above your estimated resting metabolism.
Check a future date
Choose a projection period and use the day slider to compare estimated fat change, remaining fat mass, and body fat percentage on a future date.
How to use this fat loss calculator
- Enter your current body weight and body fat percentage.
- Enter the calories you usually eat each day.
- Add calories burned from walking, training, work, or other activity.
- Compare the estimated change per day, week, and month.
- Choose a projection period and move the slider to check a date.
The calculator estimates resting metabolism from your body composition, then treats your entries as steady daily averages and turns the resulting calorie balance into a fat-equivalent estimate. It is a useful way to compare plans, but real scale and body-fat changes can also reflect water, glycogen, lean tissue, changing energy needs, and how closely a routine matches its daily average.
Fat loss calculator FAQ
How is resting metabolism estimated?
Your current body weight and body fat percentage estimate the calories your body burns at rest. This is a starting point, not your complete daily energy expenditure.
What counts as additional calories?
Additional calories can come from a walk, gym session, sports, physical work, or any other movement you want to count beyond your estimated resting metabolism.
How accurate is the estimate?
The result is an estimate based on your daily averages and estimated resting metabolism. Water weight, lean mass, changing energy needs, food tracking accuracy, and consistency can all make actual results differ.
Why is body fat percentage required?
It is used with your body weight to estimate resting metabolism. Use your best current estimate and treat the result as a useful starting point, not a medical measurement.