What Is BMI and How Is It Calculated?

BMI, or body mass index, is a quick comparison of weight and height. It is often used as a screening tool for adults.

The metric formula is simple: weight in kilograms divided by height in meters squared. For example, someone who weighs 70 kg and is 1.75 m tall has a BMI of about 22.9. That number falls in the commonly used healthy-weight range for adults.

BMI categories

Adult BMI categories are usually under 18.5 for underweight, 18.5 to 24.9 for healthy weight, 25 to 29.9 for overweight and 30 or above for obesity range. These categories can help identify patterns in large populations, but they should not be the only measure used for an individual person.

Limits of BMI

BMI does not directly measure fat, muscle, bone density or fat distribution. A muscular person can have a high BMI without having high body fat, while an older adult may have a normal BMI but low muscle mass. Pregnancy, illness and growth in children also require different interpretation.

Use the Autivae BMI calculator as a quick starting point, then consider other health markers and professional advice for meaningful decisions.