BMI Calculator

Units:
Weight:
lbs
Height:
ft
in
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About BMI Calculator

This BMI calculator is a tool created by our team at JustFit to help you determine your BMI based on your inputted numbers. That way, you can make informed decisions about your health and take appropriate steps to maintain a healthy weight!

What is BMI

Body Mass Index (BMI) is a way to determine if someone is in a healthy weight category for their height. The higher these numbers are, the higher the BMI is.

Here are the four main categories that you may fall under, based on your BMI:
  • Underweight: BMI is < 18.5
  • Normal weight: BMI is 18.5 - 25.0
  • Overweight: BMI is 25 - 30.0
  • Obese: BMI is > 30

How Your BMI is Calculated

Calculating BMI is done using a BMI formula. It can calculate in both metric and imperial units, using a different set of formulas. Using guidelines from the Centers For Disease Control and Prevention (CDC), here is how to calculate your BMI if you are:
  • Using Imperial Units

    Formula: weight (lb) / [height (in)]2 x 703
    Following the imperial unit system, you will use your weight in pounds (lb) divided by your height in inches (in) squared. This is followed by multiplying the numbers by 703, a conversion factor.
  • Using Metric Units

    Formula: weight (kg) / [height(m)]2
    Formula: weight (kg) / [height(cm)]2 x 10,000
    The formula is to use your weight in kilograms (kg) divided by your height in meters (m) squared. You may also use the alternative formula which measures your height in centimeters (cm) instead.

BMI Chart

Another way of finding your BMI level is to use a BMI Chart. You may refer to the chart below. Start by finding your weight (the closest number) first either in pounds or kilograms. Then, move down the column until you find the row that best represents your height in feet and inches or in meters. This will be an estimated number of your BMI.
height
BMI chart with height, weight and bmi metrics
weight

Limitations of BMI

While BMI is widely used and can be a useful indicator of whether you have a healthy weight, it has its own limitations.
As it is based on height and weight only, it is not an accurate measure of body fat content. It also doesn't take factors like muscle mass, bone density, age, gender, ethnicity and activity level into account. Thus, it can be useful as a screening tool for obesity but not a diagnostic measure for it.

BMI Calculator FAQ

Who should use BMI calculator?

Is BMI a reliable indicator of health?

Can BMI be used for children and teenagers?

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