Calculate your Body Mass Index with age adjustment for children & teens
Adults (20+ years) use standard ranges. Children & teens (2–19) are age-adjusted.
| Category | Adults (20+) | Children/Teens (2–19) |
|---|---|---|
| Underweight | < 18.5 | < 5th percentile |
| Healthy Weight | 18.5 – 24.9 | 5th – 85th percentile |
| Overweight | 25.0 – 29.9 | 85th – 95th percentile |
| Obese | ≥ 30.0 | ≥ 95th percentile |
Use our advanced BMI calculator to quickly calculate your Body Mass Index (BMI) and understand your weight category. This tool supports adults, children, and teenagers with age-based BMI interpretation for improved accuracy. Instantly determine whether you are underweight, normal weight, overweight, or obese. 100% free, private, and browser-based — no data is stored or shared.