What Is BMI?
Body Mass Index (BMI) is a simple screening measure that estimates whether your weight is healthy relative to your height. It's calculated by dividing weight in kilograms by height in meters squared (BMI = kg / m²). While BMI doesn't account for muscle mass, bone density, or body composition, it remains a widely used quick reference for population-level health screening and is used by doctors as a starting point for further conversation.
BMI Categories
The standard adult BMI categories are: Underweight (below 18.5), Normal weight (18.5–24.9), Overweight (25–29.9), and Obese (30 and above). Enter your height and weight in either metric or imperial units and this calculator converts automatically and tells you which category you fall into.
FAQ
Is BMI accurate for everyone?
BMI is a useful general screening tool but can be less accurate for athletes with high muscle mass, older adults, pregnant women, and children. It should be considered alongside other health measures, not as a standalone diagnosis.
How is imperial BMI calculated?
This calculator converts pounds to kilograms (× 0.453592) and inches to meters (× 0.0254) before applying the same BMI = kg / m² formula, so results are identical regardless of the units you choose.
What should I do if my BMI is outside the normal range?
Consult a healthcare professional for personalized advice — BMI is only a starting point and doesn't capture your full health picture.