BMI Calculator - Free Online Body Mass Index Calculator

Check your Body Mass Index in seconds

This free BMI calculator helps you quickly estimate your Body Mass Index using metric or imperial units. BMI is a simple screening tool used to classify adults into underweight, normal weight, overweight, and obese categories based on height and weight.

How to use this BMI calculator

1. Enter your weight and select the correct unit (kilograms or pounds).
2. Enter your height and choose centimeters, meters, feet, or inches.
3. Click Calculate BMI to see your BMI value, category, and a short explanation.

Standard adult BMI categories

• Underweight: BMI less than 18.5
• Normal weight: BMI 18.5 – 24.9
• Overweight: BMI 25.0 – 29.9
• Obese: BMI 30.0 and above

Important notes

BMI is a general guideline and does not directly measure body fat. It may not be accurate for athletes, very muscular individuals, pregnant people, or some medical conditions. Always discuss health concerns with a qualified healthcare professional.

FAQ

Is BMI enough to assess my health?

No. BMI is only one indicator. Lifestyle, diet, medical history, and other measurements are also important.

Can I use this BMI calculator for children?

No. Child and teen BMI is interpreted differently using age- and sex-specific growth charts. This tool is intended for adults.