BMI Calculator - Free Body Mass Index Calculator
Calculate your Body Mass Index (BMI), estimate body fat percentage, determine daily calorie needs, and discover your healthy weight range with our comprehensive BMI calculator.
Basic Measurements
Body Fat Estimation (Optional)
Activity Level
Your BMI Result
Healthy range: 53.5 - 72 kg
BMR (cal/day)
Daily Calories
About Our BMI Calculator
Our BMI calculator is a comprehensive tool that goes beyond basic Body Mass Index calculation. It provides a complete health assessment including body fat estimation, BMR calculation, and personalized recommendations based on your results.
Body Mass Index (BMI) is a widely used screening tool that helps assess whether your weight is appropriate for your height. While BMI doesn't directly measure body fat, it provides a useful starting point for understanding your weight status and potential health risks.
Key Features of Our BMI Calculator:
- Accurate BMI Calculation - Uses the standard WHO formula for precise results
- Body Fat Estimation - Navy method using waist, neck, and hip measurements
- BMR Calculator - Determines your daily calorie needs based on activity level
- Healthy Weight Range - Shows your ideal weight range for optimal health
- Waist-to-Height Ratio - Additional health risk assessment metric
- Personalized Health Tips - Customized advice based on your BMI category
Understanding BMI Categories:
Underweight (BMI < 18.5)
May indicate malnutrition or underlying health conditions
Normal Weight (BMI 18.5-24.9)
Associated with lowest risk of weight-related health problems
Overweight (BMI 25-29.9)
Increased risk of cardiovascular disease and diabetes
Obese (BMI ≥ 30)
Significantly increased health risks requiring medical attention
Frequently Asked Questions About BMI
How is BMI calculated?
BMI is calculated using the formula: BMI = weight (kg) ÷ [height (m)]². For imperial units, the formula is: BMI = 703 × weight (lb) ÷ [height (in)]². Our calculator automatically handles both metric and imperial conversions.
What is a healthy BMI range?
According to the World Health Organization (WHO), a healthy BMI for adults ranges from 18.5 to 24.9. However, optimal BMI can vary based on factors like age, muscle mass, bone density, and ethnicity.
Is BMI accurate for everyone?
BMI is a useful screening tool but has limitations. It doesn't distinguish between muscle and fat mass, so athletes and muscular individuals may have high BMI despite low body fat. It's also less accurate for elderly individuals, children, and certain ethnic groups.
What is body fat percentage and how is it estimated?
Body fat percentage represents the proportion of your body weight that comes from fat tissue. Our calculator uses the Navy method, which estimates body fat using waist, neck, and hip measurements. This provides a more accurate assessment of body composition than BMI alone.
What is BMR and why is it important?
Basal Metabolic Rate (BMR) is the number of calories your body needs to maintain basic physiological functions at rest. Understanding your BMR helps determine your daily calorie needs for weight maintenance, loss, or gain based on your activity level.
How often should I check my BMI?
For general health monitoring, checking your BMI monthly or quarterly is sufficient. Focus on long-term trends rather than daily fluctuations. If you're actively trying to lose or gain weight, weekly measurements can help track progress.
What should I do if my BMI is outside the normal range?
If your BMI indicates underweight, overweight, or obesity, consider consulting with a healthcare professional. They can provide personalized advice considering your overall health, medical history, and individual circumstances. Our calculator provides general guidance, but professional medical advice is always recommended for significant health decisions.
Can BMI be used for children and teenagers?
BMI calculation for children and teenagers requires age and sex-specific percentilesrather than the standard adult categories. Our calculator is designed for adults (18+ years). For children and teens, consult pediatric growth charts and healthcare providers.