Calories to Lose a Pound Calculator

About this calculator

Losing one pound of body fat requires burning roughly 3,500 more calories than you consume, a figure derived from the approximate energy density of adipose tissue. Spreading that total deficit over a chosen daily calorie deficit gives the number of days needed — for example, a 500-calorie daily deficit takes about 3,500 ÷ 500 = 7 days to lose one pound.

This estimate is a widely used planning tool in nutrition and fitness coaching, letting people set a realistic daily calorie target based on a weight-loss timeline, or check how long a given deficit will take to show results. It's an approximation rather than a precise physiological law — actual fat loss varies with metabolism, water retention, and body composition — but it remains the standard rule of thumb used by dietitians, trainers, and calorie-tracking apps.