{"uid":"cap_CFBDcQQEnUSOKpJjmVltt","slug":"bmi-calculator-with-who-category-and-healthy-weight-range-fc320922","name":"BMI Calculator with WHO Category and Healthy Weight Range","description":"Body mass index from weight and height, metric or imperial, with the WHO adult category and the 18.5 to 24.9 weight range.","url":"https://fitness-calc.x402tookit.com/bmi?utm_source=zero.xyz","method":"GET","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method"],"properties":{"type":{"type":"string","const":"http"},"method":{"enum":["GET"],"type":"string"},"queryParams":{"type":"object","required":["weight"],"properties":{"age":{"type":"number","description":"Age in years (BMI categories apply to adults 20 and over)"},"units":{"type":"string","description":"metric (default: kg and cm) or imperial (lb, feet and inches)"},"height":{"type":"number","description":"Height in cm (metric)"},"weight":{"type":"number","description":"Weight in kg, or pounds if units=imperial"},"heightFt":{"type":"number","description":"Feet (imperial)"},"heightIn":{"type":"number","description":"Inches (imperial; total inches if heightFt is omitted)"}}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object","properties":{"bmi":{"type":["null","number"]},"asOf":{"type":["null","string"]},"source":{"type":["null","string"]},"reasons":{"type":["array","null"],"items":{"type":"string"}},"summary":{"type":["null","string"]},"verdict":{"type":["null","string"]},"category":{"type":["null","string"]},"degraded":{"type":["boolean","null"]},"heightCm":{"type":["null","number"]},"weightKg":{"type":["null","number"]},"disclaimer":{"type":["null","string"]},"notChecked":{"type":["array","null"],"items":{"type":"string"}},"kgToReachNormalMax":{},"kgToReachNormalMin":{},"healthyWeightRangeKg":{"type":["null","object"],"properties":{"max":{"type":["null","number"]},"min":{"type":["null","number"]}}},"healthyWeightRangeLb":{"type":["null","object"],"properties":{"max":{"type":["null","number"]},"min":{"type":["null","number"]}}}}}}}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.02","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.02/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.02","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.02","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_34A6tll-aOSKstKKU5rBu","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.02","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Calculates body mass index from weight and height (metric or imperial), returns the WHO adult category, and the healthy weight range for normal BMI (18.5–24.9).","exampleAgentPrompt":"Can you calculate my BMI? I weigh 185 pounds and I'm 5 feet 11 inches tall — also tell me what WHO category I fall into and how far I am from a healthy weight.","exampleUseCases":[{"title":"Personal BMI health check","prompt":"What's my BMI? I'm 72 kg and 175 cm tall. Tell me my WHO category and the healthy weight range for my height."},{"title":"Imperial units weight check for fitness app","prompt":"Calculate BMI for someone who weighs 220 pounds and is 6 feet 1 inch tall — use imperial units and tell me how many pounds they'd need to lose to reach a normal BMI."},{"title":"Pediatric-adjacent adult screening","prompt":"I'm 25 years old, 58 kg, and 163 cm. What's my BMI, which WHO category does that put me in, and what's my healthy weight range in both kg and pounds?"}],"resultDescription":"Returns the computed BMI value (number), the WHO adult category (e.g. Underweight, Normal weight, Overweight, Obese), normalized height in cm and weight in kg, the healthy weight range for BMI 18.5–24.9 in both kg and lb, how many kg to gain or lose to reach the normal range boundaries, a plain-language summary, and an optional disclaimer. Also includes a data source and timestamp.","failureModes":["Missing required weight parameter returns an error","Invalid or negative weight/height values may return null BMI","Non-numeric input for weight or height causes a validation failure","Units mismatch (e.g. passing kg weight with imperial flag) may produce implausible results","BMI categories are for adults 20+; results may include a note when age is below 20"],"whenToPreferThis":"Choose this endpoint when you need a quick, standards-based BMI calculation with a WHO category label and healthy weight range targets — especially useful for fitness apps, health screening workflows, or coaching agents that need to advise users on weight goals. Supports both metric and imperial inputs natively, making it versatile for US and international users without manual unit conversion.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-26T21:27:48.868Z","isFirstParty":false,"canonicalSlug":"bmi-calculator-with-who-category-and-healthy-weight-range-fc320922"}