BMI Calculator
Use this BMI calculator to find your Body Mass Index based on your height and weight. BMI is a quick screening tool used worldwide to estimate whether your weight is healthy for your height.
What is BMI?
Body Mass Index (BMI) is a value derived from a person's weight and height. The formula divides body mass by the square of body height (kg/m²). Although BMI does not directly measure body fat, it correlates well with more direct measures and is used as a low-cost first screening for weight categories that may lead to health problems.
BMI categories defined by the World Health Organization are: Underweight (<18.5), Normal (18.5–24.9), Overweight (25–29.9), and Obesity (30 or higher).
How is it calculated?
The metric BMI formula is:
BMI = weight (kg) / height (m)²
For example, a person 175 cm tall weighing 70 kg has a BMI of 70 / (1.75 × 1.75) = 22.9, which falls in the Normal range.
Frequently Asked Questions
- Is BMI accurate for athletes?
- BMI does not distinguish between fat and muscle. Highly muscular individuals can have a high BMI without excess fat. For more accurate body composition, use a Body Fat or Lean Body Mass calculator.
- What is a healthy BMI?
- A BMI between 18.5 and 24.9 is generally considered healthy for adults.
- Does BMI apply to children?
- Adult BMI categories should not be used for children. Pediatric BMI uses age- and sex-specific percentiles.