BMI Calculator
Calculate your Body Mass Index and understand your health category.
Body Mass Index (BMI) is one of the most widely used screening tools to assess whether a person has a healthy body weight relative to their height. Developed by Belgian mathematician Adolphe Quetelet in the 19th century, BMI has become a standard metric in healthcare worldwide.
The formula is simple: BMI = weight (kg) / height² (m²). Our calculator supports both metric (kg/cm) and imperial (lbs/ft) units, automatically converting as needed. The result places you into one of four categories: Underweight (below 18.5), Normal weight (18.5–24.9), Overweight (25–29.9), or Obese (30 and above).
While BMI is a useful screening tool, it has limitations. It doesn't distinguish between muscle mass and fat mass, so athletes and very muscular individuals may have a high BMI without excess body fat. Similarly, older adults may have a normal BMI but carry excess fat. For a comprehensive health assessment, BMI should be used alongside other measurements like waist circumference, body fat percentage, and overall fitness level.
BMI is recommended by the WHO and healthcare providers worldwide as a quick screening tool for weight-related health risks. Our calculator works instantly in your browser with no data stored or transmitted.
- Enter your height and weight
- Click Calculate BMI
- View your BMI value and health category
- BMI is a screening tool, not a diagnostic tool. Consult a healthcare provider for a complete assessment.
- For children and teens, BMI is age and sex-specific and is called BMI-for-age.
- Athletes may have a high BMI due to muscle mass — consider body fat percentage as an additional metric.
- A healthy BMI range is 18.5 to 24.9 for most adults.
- Track your BMI over time to monitor weight management progress.