BMI Calculator FAQ

To calculate your BMI, divide your weight in kilograms by your height in meters squared. For example, if you weigh 70 kg and are 1.75 m tall: BMI = 70 ÷ (1.75 × 1.75) = 22.9. You can also use our free online BMI calculator above for instant results without manual calculations. The formula is: BMI = weight (kg) ÷ [height (m)]²

A healthy BMI for adults is typically between 18.5 and 24.9. This range is associated with the lowest risk for weight-related health problems. However, BMI should be considered alongside other health indicators such as waist circumference, body composition, and overall health status.

Our BMI calculator is mathematically accurate for the calculation itself. However, BMI accuracy depends on correct height and weight measurements. BMI doesn't distinguish between muscle and fat, so it may not be accurate for athletes or very muscular individuals. For best results, use accurate measurements and consider BMI as one of many health indicators.

Your BMI number indicates your weight category: Underweight (below 18.5), Normal weight (18.5-24.9), Overweight (25-29.9), or Obese (30+). However, BMI is a screening tool and doesn't directly measure body fat. Consult a healthcare professional to understand what your specific BMI means for your health.

BMI Prime is your BMI divided by 25 (the upper limit of normal BMI). It's expressed as a ratio where 1.0 equals the upper limit of healthy BMI. For example, a BMI of 20 equals 0.8 BMI Prime (20÷25). BMI Prime makes it easier to see how far you are from the healthy range.

A normal BMI is between 18.5 and 24.9. This range is associated with the lowest risk for weight-related health problems. However, BMI should be considered alongside other factors like age, gender, muscle mass, and overall health status.

BMI works differently for children. While the formula is the same, children's BMI is interpreted using age and gender-specific percentiles rather than fixed ranges. Adult BMI ranges don't apply to children. Use our BMI calculator for children to get age-appropriate results.

BMI is important because it's a quick, inexpensive screening tool that helps identify potential weight-related health risks. It's widely used by healthcare professionals and researchers to track population health trends. However, BMI should be used alongside other health indicators for a complete health assessment.

BMI results fall into categories: Underweight (below 18.5), Normal weight (18.5-24.9), Overweight (25-29.9), and Obese (30+). However, BMI is a screening tool, not a diagnostic tool. It doesn't account for muscle mass, bone density, or body fat distribution. For personalized health guidance, consult with a healthcare professional.

Use a BMI calculator when you want a quick assessment of your weight status, are starting a fitness or weight management program, or need to track changes over time. However, remember that BMI is a screening tool, not a replacement for professional medical advice.

BMI (Body Mass Index) is a measure of body fat based on height and weight that applies to adult men and women. It doesn't measure body fat directly, but research shows that BMI correlates with direct measures of body fat. BMI is an inexpensive and easy screening method for weight category—underweight, healthy weight, overweight, and obesity.

The BMI formula and ranges are the same for men and women. However, men typically have higher muscle mass and lower body fat than women, so the same BMI may represent different body compositions. Women also have different fat distribution patterns. These factors should be considered when interpreting BMI.

No, BMI doesn't distinguish between muscle and fat. People with high muscle mass (athletes, bodybuilders) may have high BMI despite low body fat. This is called 'normal weight obesity' in reverse. For muscular individuals, body fat percentage or other measures may be more appropriate.

BMI correlates with certain health risks, but it's not a perfect predictor. Higher BMI is associated with increased risk for conditions like diabetes, heart disease, and sleep apnea, but many other factors (genetics, lifestyle, other health conditions) play important roles. Always consider BMI as part of a comprehensive health assessment.

The healthy BMI range (18.5-24.9) applies to most adults aged 20-65. For older adults (65+), slightly higher BMI may be acceptable due to age-related changes in body composition. For children and teens, BMI is interpreted using age and gender-specific percentiles rather than fixed ranges.