BMI Calculator
Calculate your Body Mass Index and see what category you fall into. BMI is one screening number — read the notes below to understand what it does and doesn't tell you.
At BMI 27–29.9 you typically qualify for GLP-1 medications if you have at least one related condition (type 2 diabetes, hypertension, sleep apnea, or dyslipidemia).
BMI categories
| Category | BMI range |
|---|---|
| Underweight | Below 18.5 |
| Normal weight | 18.5 – 24.9 |
| Overweight | 25.0 – 29.9 |
| Obesity class I | 30.0 – 34.9 |
| Obesity class II | 35.0 – 39.9 |
| Obesity class III | 40.0 and above |
The WHO uses adjusted cutoffs (overweight ≥23, obesity ≥27.5) for screening in many Asian populations because cardiometabolic risk rises at lower BMIs.
Related guides
BMI is one signal. These guides cover the rest of the picture — what BMI misses, and the habits that actually move it.
Frequently asked about BMI
What is a healthy BMI range?
The standard 'normal' range is 18.5 to 24.9. But BMI is a screening number, not a diagnosis — a 'normal' BMI with high waist circumference, high A1C, or high blood pressure is still cause for concern, and an 'overweight' BMI in a muscular person is often not.
What BMI do you need to qualify for Wegovy or Zepbound?
FDA labels and most insurers require a BMI ≥30, or ≥27 with at least one related condition (type 2 diabetes, hypertension, sleep apnea, or dyslipidemia). Some cash-pay telehealth programs prescribe compounded semaglutide or tirzepatide at lower BMIs.
Is BMI accurate for women?
The formula and cutoffs are the same for men and women, but women typically carry more essential body fat than men at the same BMI. Body composition tools (DEXA, bioimpedance) give a clearer picture, especially around the overweight/obese boundary.
How often should I recalculate my BMI?
Monthly is plenty during active weight loss. BMI changes slowly because weight changes slowly — daily recalculation just amplifies normal water-weight noise.
Does BMI work for children?
No, not with adult cutoffs. Children and teens use age-and-sex-specific percentile charts from the CDC or WHO. A pediatrician interprets those rather than the simple adult ranges.