BMI Calculator
Calculate your BMI instantly with our free Body Mass Index calculator. Get your BMI category, ideal weight range, and personalized health insights.
BMI Categories
- Underweight (BMI < 18.5): May indicate malnutrition or underlying health conditions.
- Normal weight (BMI 18.5–24.9): Associated with the lowest health risk for most people.
- Overweight (BMI 25–29.9): Increased risk of cardiovascular disease and type 2 diabetes.
- Obese Class I (BMI 30–34.9): High risk — lifestyle changes and medical guidance recommended.
- Obese Class II (BMI 35–39.9): Very high risk — professional intervention strongly advised.
- Obese Class III (BMI ≥ 40): Extremely high risk — immediate medical attention required.
Limitations of BMI
BMI does not distinguish between muscle and fat, nor does it account for fat distribution. Waist-to-hip ratio and body fat percentage provide additional context. Always consult a healthcare professional for a comprehensive assessment.
Frequently Asked Questions
What is BMI and how is it calculated?
BMI (Body Mass Index) is a screening tool that estimates body fat based on your weight and height. The formula is: BMI = weight(kg) / (height(m))². It helps identify potential health risks associated with weight.
What is a healthy BMI range?
A healthy BMI for most adults ranges from 18.5 to 24.9. Below 18.5 is considered underweight, 25–29.9 is overweight, and 30+ is obese. However, BMI does not account for muscle mass, bone density, or fat distribution.
Is BMI accurate for everyone?
No. BMI is a useful screening tool but has limitations. Athletes with high muscle mass may have a high BMI without excess fat. Older adults may have a normal BMI but low muscle mass. Always consult a healthcare provider for a complete assessment.
How can I improve my BMI?
Focus on sustainable habits: eat a balanced diet rich in whole foods, exercise regularly (150+ minutes of moderate activity per week), get adequate sleep (7–9 hours), and manage stress. Avoid crash diets — aim for 0.5–1 kg weight loss per week.