Calculate your Body Mass Index instantly and get personalized health insights. Free, accurate, and 100% private.
Body Mass Index (BMI) is a measurement of body fat based on height and weight that applies to adult men and women. It's one of the most widely used indicators to assess whether a person has a healthy weight for their height.
BMI = Weight (kg) / Height (m)². The result helps categorize you into weight ranges: underweight, normal weight, overweight, or obese. Understanding your BMI is the first step toward making informed health decisions and tracking your fitness journey.
Why calculate BMI regularly? Tracking your BMI helps you monitor health changes, set realistic fitness goals, and identify potential health risks early. Whether you're working on weight loss, maintaining health, or improving fitness, knowing your BMI gives you a concrete benchmark to measure progress.
Your BMI
Ideal Weight Range
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A healthy BMI ranges from 18.5 to 24.9. This range is associated with lower health risks. BMI below 18.5 is underweight, 25-29.9 is overweight, and 30+ is obese. However, BMI is just one health indicator—consult a healthcare provider for personalized advice.
BMI is a useful screening tool for most adults, but it has limitations. It doesn't distinguish between muscle and fat, so athletes may have high BMI despite being fit. It also doesn't account for bone density or body composition. For a complete health assessment, combine BMI with other measurements and consult a healthcare professional.
Monthly BMI calculations are ideal for tracking progress. Calculate at the same time each month (morning is best after using the restroom) wearing minimal clothing on a calibrated scale. This consistency helps you spot trends and stay motivated on your health journey.
The BMI formula is: Weight (kg) ÷ Height (m)². For imperial: Weight (lbs) ÷ Height (inches)² × 703. Our calculator uses this scientifically validated formula to give you accurate results instantly.
BMI changes as your weight changes. Weight fluctuations due to water retention, food intake, or hormones can temporarily affect BMI by 1-2 points. For meaningful tracking, focus on monthly trends rather than daily changes. Combine this calculator with our Calorie Calculator for better results.
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