Body Mass Index Calculator: Wolfram Alpha

Using a BMI calculator such as the one on this page, you enter your weight and height measurements. If you need to convert between units of weight, use our kilos and pounds converter. For example, a person with a lot of muscle might have a higher BMI, when their body is actually perfectly healthy, due to the fact that muscle weighs more than fat. Large-size, field-event athletes, body-builders, weight lifters, heavy weight wrestlers and boxers, and professional football players are all at risk of being misclassified.

Weight is referred to as "mass" in medical literature, while height is often called "stature". Of course, in our online BMI calculator you can enter either SI units or imperial metrics for height (feet and inches) as well as weight pounds for weight. In general, BMI is useful when applied to adults, but may be ill-suited when used for young children or even teenagers where the waist to hip ratio and body fat estimates may be more informative.

The CDC and WHO now use similar BMI range charts as below to evaluate the weight of adults aged 20 and over given his or her height. The Centers for Disease Control (CDC) and the World Health Organization (WHO) recognize that people who are overweight or underweight are at higher risk for certain health conditions. BMI is used as an indicator of the relative healthiness of a person. Numeric BMI values correspond to weight categories including underweight, healthy weight, overweight and obese. If you need other units of measure the calculator will convert among units for you. Note that you need to use kg and meters the standard units for the BMI formula are kg and meters.

Body mass index (BMI) is a measure of body fat based on height and weight that applies to adult men and women. This easy-to-use calorie calculator gives you a personalised estimate based on your age, sex, weight, height, and activity level. Some guidelines just look at waist circumference to measure tummy fat. These categories are the same no matter what gender and ethnicity you are and if you are muscular. Use measurements in the same units – so centimetres (cms) or inches. To calculate your waist to height ratio, measure your waist and divide it by your height.

While BMI can be a useful tool when considering large populations, it is not reliable for determining leanness or corpulence in individuals. BMI prime is the ratio of a person's measured BMI to the upper limit of BMI that is considered "normal," by institutions such as the WHO and the CDC. Unlike adult BMI ranges, children's BMI is interpreted using age and gender-specific percentiles that account for normal growth and development patterns. Female athletes may also have different BMI interpretations due to muscle mass variations. While the basic BMI formula remains consistent across different populations, interpretation and application may vary based on age, gender, ethnicity, and specific health conditions. Our body mass index calculator automatically handles both metric (cm and kg) and imperial units (feet/inches and pounds), making it easy to calculate BMI regardless of your preferred measurement system.

If you're worried about your child's weight you should speak to your doctor – especially if they fall outside the healthy centile range. Because children are still growing, and boys and girls develop at different times, their BMI is measured differently. You should speak to your doctor about how to lose weight and bring down your BMI to a healthy level. The National Cancer Institute found that severe obesity can reduce life expectancy by 6 to 13 years.  link  of 40 or above means you’re in the range of severe class 3 obesity – which can have a high chance of affecting your health.

BMI is a general guideline but may not account for factors like muscle mass or body composition. Wikipedia lists alternative BMI ranges and categories for specific Asian populations. Your input can include complete details about your gender, height and weight, or you can add, remove and modify values and parameters using a simple form interface. Calculations can take your gender into account and produce charts showing where your BMI falls in relation to the normal range for adults. For children and young people - between 2 to 18 years old – the children’s BMI calculator considers age and gender as well as height and weight. Because muscle weighs more than fat, muscular people - such as weight trainers and athletes - may be a healthy weight even though their BMI is classed as obese.

The BMI calculator for men follows the standard BMI formula, but men typically have higher muscle mass and lower body fat percentages compared to women at the same BMI level. Women's body composition changes throughout life stages - during puberty, pregnancy, and menopause. Understanding these differences helps ensure more accurate health assessment and appropriate medical guidance. The BMI index calculation remains the same globally, but interpretation may vary slightly based on ethnicity, age, and specific health guidelines used by different countries' health systems. For imperial measurements, the additional multiplication by 703 converts the result to match the metric BMI scale.