{"openapi":"3.1.0","info":{"title":"Body Metrics API","version":"1.0.0","description":"Anthropometric body-metrics maths as an API, computed locally and deterministically. The body-surface-area endpoint computes the body surface area in square metres from height and weight by five established formulas — Mosteller √(height·weight/3600), DuBois, Haycock, Gehan-George and Boyd — with their average, the figure used for chemotherapy dosing and cardiac index. The lean-mass endpoint estimates lean body mass from height, weight and sex by the Boer, James and Hume formulas, with the fat mass and body-fat percent that follow. The waist-ratio endpoint computes the waist-to-hip ratio (fat distribution) and the waist-to-height ratio — where keeping your waist under half your height is the simple healthy rule — with WHO-style risk bands. Heights and circumferences are in centimetres, weight in kilograms. Everything is computed locally and deterministically, so it is instant and private. Ideal for health, fitness, clinical, telemedicine and wellness app developers, body-composition and dosing tools, and health education. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is body surface area, lean mass and waist ratios; for BMI, body fat and ideal weight use a BMI API and for BMR and TDEE a BMR API.","contact":{"name":"PremiumApi","url":"https://www.oanor.com/by/premiumapi"}},"servers":[{"url":"https://api.oanor.com/bodymetrics-api","description":"oanor gateway"}],"tags":[{"name":"Body Metrics"},{"name":"Meta"}],"components":{"securitySchemes":{"oanorKey":{"type":"apiKey","in":"header","name":"x-oanor-key","description":"Get your key at https://www.oanor.com/developer/keys"}}},"security":[{"oanorKey":[]}],"paths":{"/v1/body-surface-area":{"get":{"operationId":"get_v1_body_surface_area","tags":["Body Metrics"],"summary":"Body surface area","description":"","parameters":[{"name":"height","in":"query","required":true,"description":"Height (cm)","schema":{"type":"string"},"example":"180"},{"name":"weight","in":"query","required":true,"description":"Weight (kg)","schema":{"type":"string"},"example":"75"}],"security":[{"oanorKey":[]}],"responses":{"200":{"description":"OK","content":{"application/json":{"example":{"data":{"note":"Body surface area (m²). 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