Free BMI Calculator & Healthy Weight Range Online
Calculate BMI with WHO adult classification, healthy weight range, Ponderal Index, and resting Basal Metabolic Rate using Mifflin-St Jeor equation. — 100% free online utility, zero sign-up, zero paywalls, and private client-side processing.
Standard adult BMI cutoffs apply to men and women aged 18+. Athletes and bodybuilders should also evaluate body fat percentage, as muscle density skews BMI upward.
How It Works
Select Unit System
Choose Metric (kg/cm) or Imperial (lb/ft) for your measurements.
Enter Height
Input your height in centimeters or feet and inches.
Enter Weight
Input your current body weight in kilograms or pounds.
Review Health Metrics
See your BMI, WHO category, healthy weight range, Ponderal Index, and BMR.
Frequently Asked Questions
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