BMI Calculator

Calculate your Body Mass Index in seconds using imperial or metric units. Your BMI is a quick screening tool that places your weight relative to your height into one of four categories — underweight, normal, overweight, or obese.

Height

Weight

Your BMI

—

<18.5

18.5-24.9

25-29.9

30+

Underweight • Normal • Overweight • Obese

What your BMI score means

BMI is calculated by dividing your weight in kilograms by your height in meters squared. A BMI under 18.5 is considered underweight, 18.5-24.9 is the normal range, 25-29.9 is overweight, and 30 or above falls into the obese category. Athletes and very muscular individuals may register as "overweight" despite low body fat, since BMI doesn't distinguish muscle from fat.

BMI is a screening tool, not a diagnostic measure. It doesn't account for muscle mass, bone density, body composition, or fat distribution. For a more accurate picture, pair BMI with body fat percentage and waist circumference.