BMI Calculator

Calculate your Body Mass Index using WHO and CDC standards.

Your Measurements

Your BMI

Enter your measurements above
UnderweightNormalOverweightObese
Healthy Weight Range
Weight to Ideal Midpoint

BMI Categories (WHO / CDC)

UnderweightBelow 18.5
Normal weight18.5 – 24.9
Overweight25.0 – 29.9
Obese class I30.0 – 34.9
Obese class II35.0 – 39.9
Obese class III40.0 and above

BMI formula (metric): BMI = weight(kg) ÷ height(m)². For imperial: BMI = 703 × weight(lbs) ÷ height(inches)².

Healthy weight range is calculated by finding the weight that gives a BMI of 18.5 (lower bound) and 24.9 (upper bound) for your height.

BMI classifications are the same for adult males and females per WHO/CDC guidelines. Children use age- and sex-specific percentile charts instead.

⚠️ BMI is a screening tool, not a diagnostic measure. It does not account for muscle mass, bone density, age-related changes, or distribution of fat. People with high muscle mass may have a high BMI without excess body fat. Consult a healthcare provider for a complete health assessment.