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Track body composition and energy needs with free health calculators: BMI, BMR from the Mifflin-St Jeor equation, daily calorie targets by activity level and body fat percentage. Standard published formulas, instant results, no account needed.
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Body composition, energy needs and daily calorie targets
These tools use the published equations and reference ranges that clinicians and nutritionists recognise, so the results line up with what you will see in a clinic or on a nutrition label. Body mass index follows the World Health Organization and CDC definitions of weight status. Basal metabolic rate is calculated with the Mifflin-St Jeor equation, and the calorie calculator adjusts that figure for activity level and for whether your goal is to maintain, lose or gain weight. Body fat percentage uses the U.S. Navy circumference method. These are screening estimates rather than medical advice, so discuss any result that concerns you with a qualified professional.
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