BMI Calculator

A Body Mass Index Calculator or BMI Calculator. Check your BMI below!
Recognized as a better way to see if a person is overweight / underweight based on height and weight.
Note: Accuracy can vary for people such as athletes, children, the elderly, endomorphic or ectomorphic frames.

What is BMI

A BMI calculator is a tool that is used to estimate an individual's body mass index (BMI) based on their height and weight. BMI is a measure of body fat based on an individual's weight in relation to their height. It is widely used as a screening tool to identify potential health risks associated with obesity and being underweight.

BMI is calculated by dividing an individual's weight by their height squared. The resulting number is then compared to a standard BMI chart to determine the individual's BMI category, such as underweight, normal weight, overweight, or obese.

Our BMI calculator is easy to use and requires only basic information: Your height and weight, and our calculator will give you an estimated BMI.

However, it's important to note that BMI calculators are not always accurate and should be used as a screening tool rather than a diagnostic tool.

When NOT to use BMI?

Here are some examples of when BMI may not be the best tool to use:

  1. Athletes and bodybuilders: BMI does not take into account muscle mass, so individuals who are very muscular may have a high BMI even though they are not overweight or obese.
  2. Elderly individuals: BMI may underestimate body fat in older individuals who have lost muscle mass, which is a common occurrence with aging.
  3. Pregnant women: BMI is not a reliable measure of body fat in pregnant women because it does not account for the weight of the fetus or the increased fluid and blood volume during pregnancy.
  4. Children: BMI charts for children and adolescents take into account age and sex as well as height and weight, but they still may not be an accurate measure of body fat in growing children.
  5. Individuals with certain medical conditions: BMI may not be a reliable indicator of health in individuals with certain medical conditions, such as those with muscular dystrophy or those who have undergone amputations.

In these cases, other measures of body fat, such as skinfold thickness, bioelectrical impedance, or dual-energy x-ray absorptiometry (DXA), may be more appropriate.

It is always best to consult with a healthcare professional to determine the most appropriate method of assessing body fat for individual cases.

How to use our BMI Calculator

Using a BMI (body mass index) calculator is a simple and straightforward process. Here are the steps to follow:

  1. Enter your height. You will need to enter your height in either centimeters or feet and inches, depending on what units you use.
  2. Enter your weight. You will need to enter your weight in either kilograms or pounds.
  3. Once you have entered your height and weight, click the "Calculate" button to see your BMI.
  4. Review your results. Your BMI will be displayed on the screen, along with an interpretation of what it means. You will also see your BMI category: underweight, normal weight, overweight, or obese.

BMI Results

BMI Score Category Suggested Steps
Below 18.5 Underweight If you are underweight, it is important to consult a doctor or a dietitian to develop a healthy eating plan and gain weight in a safe and sustainable way. This may involve consuming more protein, healthy fats, and complex carbohydrates to increase your calorie intake, as well as engaging in strength training exercises to build muscle mass.
18.5 - 24.9 Normal Maintaining a balanced diet and engaging in regular physical activity are key to staying healthy and preventing weight-related health issues. Eat plenty of fruits, vegetables, whole grains, lean proteins, and healthy fats, and aim for at least 30 minutes of moderate-intensity exercise most days of the week.
25.0 - 29.9 Overweight If you are overweight, reducing your calorie intake and increasing your physical activity levels can help you achieve a healthy weight and reduce the risk of health problems. This may involve eating a balanced, low-calorie diet that is rich in whole foods and low in processed and high-fat foods, and engaging in regular aerobic and strength training exercises to burn calories and build muscle.
Above 30.0 Obese If you are obese, it is important to consult a doctor or a dietitian to develop a weight loss plan that includes diet modifications, physical activity, and possibly medication or surgery to reduce health risks associated with obesity. This may involve eating a low-calorie, nutrient-rich diet that is high in fruits, vegetables, lean proteins, and healthy fats, and engaging in regular aerobic and strength training exercises to burn calories and build muscle.

History of BMI

Did you know... BMI (Body Mass Index) was developed by Adolphe Quetelet, a Belgian statistician, astronomer, and mathematician, in the early to mid-19th century.

Quetelet was interested in developing a simple, standardized way to measure obesity in populations.

He recognized that simply measuring body weight was not sufficient, as taller individuals would naturally weigh more than shorter individuals, even if they had the same amount of body fat.

BMI (body mass index) is sometimes called the "Quetelet Index" after its developer, Adolphe Quetelet

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