BMI Calculator
BMI is a simple height-and-weight index. It is useful for quick screening, but it does not separate muscle, fat, water, or body shape.
BMI formula
BMI is weight in kilograms divided by height in meters squared. For example, 70 kg at 170 cm gives a BMI of about 24.2.
Adult BMI categories are useful for a quick overview, but the same BMI can mean different body compositions for different people.
How to interpret BMI
A high BMI may reflect body fat, muscle mass, or both. A normal BMI can still hide a high waist circumference or low activity level.
This tool is for everyday estimation and is not medical, nutrition, or training advice. Athletes, pregnant people, children, and older adults should avoid using BMI as the only health signal.