Calculate your Body Mass Index
Categories: Underweight <18.5 · Normal 18.5–24.9 · Overweight 25–29.9 · Obese ≥30
Body Mass Index (BMI) is a widely used screening tool that estimates body fat based on a person's height and weight. Our free BMI Calculator supports both metric and imperial units and provides instant results with clear category classification. The WHO classifies BMI into four categories: underweight (below 18.5), normal weight (18.5 to 24.9), overweight (25 to 29.9), and obese (30 and above).
BMI is calculated by dividing weight by the square of height. While BMI is a useful general indicator, it does not account for muscle mass, bone density, age, or gender. Athletes may have a high BMI due to muscle rather than fat. For a complete health assessment, consult a healthcare professional. This calculator runs entirely in your browser — no health data is transmitted or stored anywhere.