Step 1: Calculating Weight Maintenance Calories
We use the official formulas for Estimated Energy Requirements provided by the Food and Nutrition Board of the Institute of Medicine of the National Academies.
Adult man (19+ years old): EER = 753.07 – 10.83 × age [y] + 6.50 × height [cm] + 14.10 × weight [kg]
Adult woman (19+ years old): EER = 584.90 – 7.01 × age [y] + 5.72 × height [cm] + 11.71 × weight [kg]
The formulas are explained in "Estimated Energy Requirements" chapter of DRI for Energy book.
We recommend selecting activity level as "sedentary" and accurately accounting for any extra energy-burning activities and exercises that are outside of typical "sedentary" lifestyle. This will be much more accurate than the generic "active" activity level, which is of course a very rough guess. You can adjust your activity level in the Me tab - Personal Info.
The resulting number, "Estimated Energy Requirements," is called Weight Maintenance Calories. This is the number of calories your body needs to maintain its current weight.
Before January 2025, we used the official formulas for Estimated Energy Requirements provided by the Food and Nutrition Board of the Institute of Medicine of the National Academies 2005 edition.
Adult man: EER = 662 - 9.53 x age (y) + PA x (15.91 x wt [kg] + 539.6 x ht [m])
Adult woman: EER = 354 - 6.91 x age (y) + PA x (9.36 x wt [kg] + 726 x ht [m])
The formulas are explained in "Energy" chapter of DRI book 2005 edition.
PA indicates activity level, and is equal to 1.0 for sedentary, 1.12 for low active, 1.27 for active, and 1.45 for very active. See more details about physical activity levels. We recommend selecting activity level as "sedentary" and accurately accounting for any extra energy-burning activities and exercises that are outside of typical "sedentary" lifestyle. This will be much more accurate than the generic "active" activity level, which is of course a very rough guess. You can adjust your activity level in the Me tab - Personal Info.
Step 2: Calculating Required Daily Calorie Deficit
Required Daily Calorie Deficit is the number of calories you need to "lose" daily. It is calculated based on the number of pounds left to lose and the number of days left until your target date.
To lose a pound of fat, you need to lose 3,500 calories. So, Required Daily Calorie Deficit is calculated as the number of pounds to lose multiplied by 3,500 calories and divided by the number of days left until your target date.
Step 3: Calculating Calorie Budget
The final step is to subtract from Weight Maintenance Calories your Required Daily Calorie Deficit. This is the number of calories your need to consume to reach your weight goal on the target date. This is the number set as your Daily Calorie Budget.
Body Fat Percentage and BMI
We do not consider body fat percentage or BMI for calculating Calorie Budget, as the formulas above are more accurate. You may want to look if your BMI is in a healthy range when you decide what your desired target weight is.