BMI (Body Mass Index) is a measure of body fat based on height and weight that applies to adult men and women. It's calculated by dividing a person's weight in kilograms by the square of their height in meters (kg/m²).

For imperial units, the formula is: (weight in pounds / (height in inches)²) x 703.

Our calculator automatically handles both metric and imperial units, so you don't need to do any conversions.

For adults, BMI is categorized as follows:

Yes, BMI interpretation for children and teens is different from adults. Instead of fixed categories, children's BMI is compared to percentiles for their age and gender.

The categories for children are:

• Underweight: BMI below the 5th percentile
• Healthy weight: BMI between 5th and 85th percentile
• Overweight: BMI between 85th and 95th percentile
• Obese: BMI at or above the 95th percentile

Our calculator automatically adjusts interpretation based on the age you enter.

Our BMI calculator uses the standard formulas endorsed by health organizations worldwide, so the calculations are mathematically accurate.

However, it's important to understand that BMI is a screening tool, not a diagnostic one. It provides a general indication of whether you're at a healthy weight, but it doesn't account for factors like muscle mass, bone density, or body composition.

We ask for gender and age to provide the most accurate interpretation of your BMI result:

• Gender: While the BMI calculation is the same for men and women, the interpretation may vary slightly due to physiological differences in body composition.
• Age: BMI interpretation is different for children and adults. For children, we use age- and gender-specific percentiles rather than fixed categories.

Yes! Our calculator allows you to easily switch between metric (centimeters and kilograms) and imperial (inches and pounds) units.

Simply click the "Metric" or "Imperial" buttons at the top of the calculator. The units will automatically update, and you can enter your measurements in your preferred system.

While BMI is a useful screening tool, it has several limitations:

• Muscle vs. Fat: BMI doesn't distinguish between muscle and fat, so athletes with high muscle mass may have a high BMI but low body fat.
• Fat Distribution: It doesn't account for where fat is located on the body, which is important for health risks.
• Age Considerations: It may not be as accurate for older adults who have lost muscle mass.
• Ethnic Differences: Some ethnic groups may have different health risks at the same BMI.
• Pregnancy: BMI is not accurate during pregnancy.

Yes, BMI can be misleading for athletes and very muscular individuals. Since muscle is denser and weighs more than fat, these individuals may have a high BMI that classifies them as overweight or obese, even though they have low body fat and are in excellent health.

If you're an athlete or have a muscular build, consider additional assessments like body fat percentage measurements or waist-to-hip ratio for a more accurate health evaluation.

For most adults, checking your BMI every 3-6 months is sufficient unless you're actively trying to change your weight. For children, regular monitoring (every 6-12 months) is recommended as they grow.

If your BMI falls outside the normal range:

• Don't panic: BMI is just one indicator of health.
• Consult a professional: Speak with a healthcare provider for personalized advice.
• Focus on habits: Instead of quick fixes, work on sustainable lifestyle changes.
• Consider other factors: Look at your eating patterns, activity levels, sleep quality, and stress management.

Our calculator provides general guidance, but individual health needs vary. Always consult with a healthcare professional for personalized recommendations.