WHO BMI Classification for adults
| Classification | BMI Range | Health risk |
|---|---|---|
| Underweight | < 18.5 | Increased |
| Normal weight | 18.5 - 24.9 | Low |
| Overweight | 25.0 - 29.9 | Increased |
| Obese | ≥ 30.0 | High |
BMI CALCULATOR
Calculate your Body Mass Index and discover your health status
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Why choose our BMI Calculator?
The most comprehensive Body Mass Index tool online
Instant calculation
Get your BMI result immediately with visual indicators and health category classification.
Age-adjusted BMI
Personalized BMI thresholds for children, adults, and seniors based on WHO guidelines.
Dual unit system
Supports both metric (kg/cm) and imperial (lbs/ft,in) measurement systems seamlessly.
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Get personalized recommendations based on WHO guidelines with BMR and TDEE calculations.
Ideal weight range
Calculate your healthy weight range and see exactly how much to gain or lose.
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Frequently Asked Questions
Everything you need to know about BMI
What is BMI?
BMI (Body Mass Index) is a measure of body fat based on height and weight. It's calculated by dividing weight in kilograms by height in meters squared (kg/m²).
What is a healthy BMI range?
A healthy BMI range for adults is 18.5-24.9. Below 18.5 is underweight, 25-29.9 is overweight, and 30+ is obese according to WHO standards.
How accurate is BMI?
BMI is a useful screening tool but doesn't directly measure body fat. It may not be accurate for athletes with high muscle mass or elderly people with muscle loss.
How do I calculate BMI manually?
For metric: BMI = weight(kg) / height(m)². For imperial: BMI = (weight(lbs) × 703) / height(inches)². Our calculator does this instantly for you.
Is BMI different for men and women?
The BMI calculation is the same for men and women, but body composition differs. Women typically have more body fat than men at the same BMI.
What's my ideal weight?
Ideal weight depends on height, age, gender, and body frame. Our calculator shows your healthy weight range based on BMI 18.5-24.9.