BMI Calculator

Calculate your Body Mass Index to determine if you're at a healthy weight. Get personalized recommendations and understand your BMI category.

Metric (kg, cm)
Imperial (lbs, in)
kg
cm

About BMI Calculator

BMI (Body Mass Index) is a measurement that uses your height and weight to determine if you're at a healthy weight for your height. While BMI is a useful screening tool, it doesn't directly measure body fat and may not account for muscle mass, bone density, and other factors. Always consult with a healthcare provider for a comprehensive health assessment.

BMI Examples

Common BMI calculations:

  • Normal BMI (70kg, 175cm)
  • Overweight (85kg, 170cm)
  • Underweight (50kg, 165cm)
  • Normal (154lbs, 5'7")

Frequently Asked Questions

BMI (Body Mass Index) is a measure of body fat based on height and weight. It's calculated by dividing a person's weight in kilograms by the square of their height in meters (kg/m²). For imperial measurements, the formula is (weight in pounds / (height in inches)²) x 703.

  • Underweight: BMI less than 18.5
  • Normal weight: BMI 18.5 to 24.9
  • Overweight: BMI 25 to 29.9
  • Obese: BMI 30 or greater
These categories are based on guidelines from the World Health Organization.

BMI is a useful screening tool but has limitations. It doesn't differentiate between muscle and fat, so athletes with high muscle mass may have a high BMI but low body fat. Similarly, older adults may have a normal BMI but higher body fat percentage. BMI should be used as one indicator among others (like waist circumference, diet, and activity level) when assessing health.

Yes, BMI interpretation is different for children and teens. For those under 20, BMI is age and sex-specific and is referred to as BMI-for-age. Growth charts from the CDC are used to determine the percentile, which indicates how a child's BMI compares to others of the same age and sex.

No, we do not store any of the data you enter into the BMI Calculator. All calculations are performed locally in your browser, ensuring your health information remains private and secure.