BMI = weight (kg) ÷ height (m)². That's it — one formula, used worldwide as a quick screening tool.
Categories
- Below 18.5 — Underweight
- 18.5–24.9 — Healthy weight
- 25–29.9 — Overweight
- 30+ — Obesity
What BMI misses
Muscle, bone density and fat distribution. Athletes often land 'overweight' while being very lean. BMI is a screening tool, not a diagnosis — pair it with waist measurement or body-fat % for the real picture.
Calculate yours with our BMI Calculator (imperial/metric), then check body fat % for the fuller story.