BMI (Body Mass Index) is a quick screening number that relates your weight to your height. Doctors use it as a first check — not a final verdict on your health, but a useful starting point.
The BMI formula
BMI = weight (kg) ÷ height (m)2
Example: 70 kg at 1.75 m → 70 ÷ (1.75 × 1.75) = 22.9.
BMI chart for adults
- Below 18.5 — Underweight
- 18.5 – 24.9 — Normal / healthy weight
- 25 – 29.9 — Overweight
- 30 and above — Obese
What counts as a "good" BMI?
For most adults, the healthy target is 18.5 to 24.9. But BMI doesn't distinguish muscle from fat — athletes and very muscular people can score "overweight" while being perfectly fit. Treat it as a signal, not a diagnosis.
Check yours in seconds
Use our free BMI Calculator: enter height and weight to get your BMI plus your healthy weight range — no sign-up needed.
Note: this is general information, not medical advice. Talk to a doctor for personal health decisions.