BMI (Body Mass Index) is the most widely used screening tool for weight status. The formula: BMI = weight (kg) ÷ height (m)². For example, 65 kg ÷ (1.70 m)² = 22.5.
WHO global standard: 18.5–24.9 normal, 25–29.9 overweight, ≥30 obese. Asian thresholds are stricter: 18.5–23.9 normal, 24–27.9 overweight, ≥28 obese — because Asian populations face higher diabetes and hypertension risk at the same BMI level.
The thresholds are the same, but interpretation differs. Women naturally carry 5–10% more body fat than men at the same BMI, so health risk is slightly lower. In fitness/aesthetic contexts, "ideal BMI" expectations also differ by gender.
BMI is a screening tool, not a diagnosis. It cannot distinguish muscle from fat (a bodybuilder at BMI 28 may be perfectly healthy), does not reflect visceral fat distribution, and children, pregnant women, and elderly need adjusted standards. Combine with waist circumference, body fat percentage, and blood work for a complete picture.
Enter your height in cm and weight in kg, click calculate. The result shows your BMI number, category (underweight/normal/overweight/obese), and a color-coded indicator. Our tool supports both WHO and Asian thresholds, plus imperial units (feet/inches, pounds).