Calorie Deficit Calculator

A calorie deficit means eating fewer calories than your body uses. This tool estimates your maintenance calories and how long a 1 lb or 2 lb per week rate would take to reach your goal weight.

Calorie deficit targets are estimates based on factors such as your age, activity level, weight, height, body fat percentage, and weight loss goal. Results may not accurately reflect individual needs for everyone, including those with high muscle mass, pregnant women, children, older adults, certain ethnic groups, or people with specific health conditions. Use this calculator as a general guide, not as a stand-alone measure of your health.

How this is calculated. Maintenance calories use the Mifflin-St Jeor equation and your activity factor. Timelines assume roughly 3,500 calories per pound of body fat — a widely used planning figure, not a guarantee. Rates faster than about 2 lb per week are generally not recommended without clinical supervision.