Free BMI Calculator – Calculate Your Body Mass Index Online Instantly

Body mass index

Measure it,
then read the room.

Enter your height and weight to get your BMI, where it falls on the scale, and what that number does and doesn't tell you.

Height

cm

Weight

kg

Height

ft in

Weight

lb

—

kg/m²

—

15

18.5

25

30

40+

Underweight Normal Overweight Obese

The full scale

Range	BMI	Category
Underweight	Below 18.5	Low body weight for height
Normal	18.5 – 24.9	Typical range for most adults
Overweight	25.0 – 29.9	Above typical range
Obese	30.0 and above	Well above typical range

BMI is a screening measure based on height and weight alone. It doesn't distinguish muscle from fat and can misread the picture for athletes, older adults, and pregnant people. Use it as a starting point, not a diagnosis, and talk to a doctor for a fuller read on your health.