Body Mass Index (BMI) is a measure of body composition based on height and weight. It helps assess whether you are underweight, normal, overweight, or obese.

How is BMI calculated?

BMI is calculated by dividing weight in kilograms by height in meters squared. For imperial units, BMI = (weight in pounds ÷ height in inches²) × 703.

Is BMI accurate for everyone?

BMI is a screening tool and does not distinguish between muscle and fat. Athletes and people with high muscle mass may have high BMI despite low body fat.

Can I use BMI to track health over time?

Yes, tracking BMI over time can help monitor general weight trends and assess potential health risks, but consult a healthcare professional for personalized guidance.

BMI Calculator

Calculate your Body Mass Index (BMI) to assess your body composition. Supports metric and imperial units for accurate health assessment.

⚠️ Note: BMI is a screening tool. For medical advice, consult a qualified healthcare professional.

Height Select unit and enter value

Weight Select unit and enter value

Understanding BMI

What is BMI?

Body Mass Index (BMI) is a measure of body composition based on height and weight. It is calculated by dividing your weight in kilograms by your height in meters squared (kg/m²). BMI serves as a screening tool to identify potential weight-related health risks but does not directly measure body fat percentage.

BMI Categories

Underweight: BMI less than 18.5
Normal Weight: BMI 18.5 - 24.9
Overweight: BMI 25 - 29.9
Obese: BMI 30 and above

How to Calculate BMI

The formula for BMI is:

BMI = Weight (kg) ÷ Height (m)²

Example: If you weigh 70 kg and are 1.75 m tall, your BMI = 70 ÷ (1.75 × 1.75) = 22.9

Limitations of BMI

Does not account for muscle mass vs. fat mass (athletes may have high BMI)
Age, gender, and ethnicity variations not considered
Does not measure visceral fat or body composition directly
Different standards for children and pregnant women
Should be used as a screening tool, not a diagnostic tool

Health Implications by Category

Underweight: May indicate malnutrition. Consult a healthcare provider.
Normal Weight: Generally associated with lower health risks. Maintain healthy habits.
Overweight: Increased risk of type 2 diabetes and heart disease. Consider lifestyle changes.
Obese: Significantly higher risk of chronic diseases. Professional consultation recommended.

Tips for Healthy Weight

Maintain a balanced diet rich in fruits, vegetables, and whole grains
Exercise regularly: aim for 150 minutes of moderate activity per week
Stay hydrated and limit sugary drinks
Get adequate sleep (7-9 hours per night)
Manage stress through relaxation techniques
Consult healthcare professionals for personalized advice

BMI Reference Chart

Category	BMI Range	Health Status
Underweight	Below 18.5	May need nutritional support
Normal Weight	18.5 - 24.9	Healthy range
Overweight	25 - 29.9	Increased health risk
Obese Class I	30 - 34.9	High health risk
Obese Class II	35 - 39.9	Very high health risk
Obese Class III	40+	Extreme health risk