Body Fat API
Body-fat-percentage and body-composition maths as an API, computed locally and deterministically. The navy endpoint applies the US Navy circumference method — for men %BF = 495/(1.0324 − 0.19077·log10(waist − neck) + 0.15456·log10(height)) − 450, and for women a formula that adds the hip measurement — to estimate body fat from a tape measure alone, returning the percentage and the fitness category (essential, athletes, fitness, acceptable or obese); a man of 178 cm with a 40 cm neck and 90 cm waist reads about 18.7 %. The deurenberg endpoint gives the BMI-based estimate %BF = 1.20·BMI + 0.23·age − 10.8·(1 if male) − 5.4 from BMI or weight and height plus age. The composition endpoint splits a total weight into fat mass and lean (fat-free) mass from a body-fat percentage. Circumferences and height are in centimetres and weight in kilograms. Everything is computed locally and deterministically, so it is instant and private. Ideal for fitness, wellness, gym, nutrition, body-tracking and health-education app developers, body-composition and progress-tracking tools, and coaching software. These are estimation formulas, not a substitute for DEXA or professional assessment. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is body-fat percentage; for body-mass index use a BMI API and for basal metabolic rate a BMR API.
api.oanor.com/bodyfat-api
