Overweight is defined as having a body mass index (BMI) of 25 to 29.9 kilograms per meters squared (kg/m2); a person’s BMI is calculated by dividing their weight by the square of their height. More specifically, a person with:[1]
- A BMI of <18.5 is “underweight”
- A BMI of 18.5 to 24.9 is “normal weight”
- A BMI of 25 to 29.9 has “overweight”
- A BMI of 30 to 34.9 has “class I obesity”
- A BMI of 35 to 39.9 has “class II obesity”
- A BMI of >40 has “class III obesity”