BMI Calculator
Enter your height and weight to get your Body Mass Index, your category, and the healthy weight range for your height.
Enter your height and weight to see your BMI.
-BMI
Healthy weight for your height
BMI categories for your height
Runs entirely on your device - nothing is ever uploaded.
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How to use the BMI calculator
- Choose Metric or US Units. Switching converts the height and weight you already entered.
- Enter your height and weight.
- Read your BMI, its category, and the healthy weight range for your height on the scale.
BMI categories
The calculator uses World Health Organization cutoffs: severe thinness (under 16), moderate thinness (16-17), mild thinness (17-18.5), healthy weight (18.5–24.9), overweight (25-30), and obese class I (30-35), class II (35-40) and class III (40+). These bands come from large population studies linking BMI ranges to health risk.
What BMI cannot tell you
BMI sees total mass, not composition: a muscular build can score "overweight" while carrying little fat. Use it together with waist measurement and the body fat calculator, and treat it as a starting point for a conversation with a clinician rather than a verdict.
This is an estimate, not medical advice or a diagnosis. Adult WHO cutoffs are a poor fit for children, pregnancy, and many athletes. The formula is weight in kilograms divided by height in meters squared, using the category bands published by the World Health Organization.
Worked example
A height of 175 cm and weight of 70 kg gives BMI = 70 ÷ 1.75² = 70 ÷ 3.0625 ≈ 22.9 - inside the 18.5–24.9 healthy band. The healthy range for that height is 18.5 × 1.75² ≈ 56.7 kg to 24.9 × 1.75² ≈ 76.3 kg. In US units, 5′9″ (69 in) and 160 lb gives BMI = 703 × 160 ÷ 69² ≈ 23.6, the same healthy band.