Measure your weight in kilograms or pounds
Measure your height in meters or inches
Use the BMI formula: BMI = weight in kg ÷ height in m²
If using pounds and inches, use: BMI = (weight in lb ÷ height in in²) × 703
Square your height before dividing
Compare your BMI to standard categories:
Underweight: below 18.5
Normal weight: 18.5 to 24.9
Overweight: 25 to 29.9
Obesity: 30 or higher