Obesity is defined as having excess body fat, usually defined by a body mass index of 30 or more.

Types

Obesity can be mild with a BMI of 30-34.9
Moderate obesity has a BMI of 35-39.9
and morbid obesity has a BMI of 40 or mor
https://www.hsph.harvard.edu/obesity-prevention-source/obesity-definition/how-to-measure-body-fatness/