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Calculate your Body Mass Index (BMI) from height and weight using metric or imperial units and view the corresponding adult BMI range.
Your health category and advice will appear here.
Body Mass Index (BMI) is a screening measure that relates an adult's weight to their height. It provides a numerical value that can be compared with commonly used adult BMI ranges. BMI is simple to calculate, but it should be interpreted as a screening measure rather than a complete assessment of health or body composition.
When weight is measured in kilograms and height is measured in meters, BMI is calculated using the following formula:
For example, an adult who weighs 70 kg and is 1.75 meters tall would have a BMI of approximately 22.9:
ToolXone's metric mode accepts height in centimeters, so the calculator converts the entered height to meters before calculating BMI.
When weight is entered in pounds and height is measured in inches, the BMI formula used by this calculator is:
ToolXone's Feet / Pounds mode allows height to be entered as feet and inches. The calculator converts the height to total inches before applying the formula.
This calculator groups adult BMI results into four ranges:
These ranges are used for adult BMI screening. A BMI result identifies the range in which the calculated value falls; it does not by itself determine a person's overall health.
Choose Metric if you want to enter height in centimeters and weight in kilograms. Choose Feet / Pounds if you want to enter height in feet and inches and weight in pounds. Enter your measurements and select Calculate BMI.
The calculator displays your BMI rounded to one decimal place, the corresponding adult BMI range, and a visual marker showing where the result falls on the calculator's BMI scale.
BMI compares weight with height and provides a convenient screening value. It can be useful for looking at weight-related categories at a general level because the calculation requires only height and weight.
However, BMI does not directly measure body fat and does not explain why a person has a particular weight. The same BMI value can occur in people with different body compositions.
BMI uses only height and weight. It does not distinguish between body fat, muscle, bone and other components of body mass. As a result, two adults with the same height and weight can have the same BMI while having different body compositions.
BMI also does not directly measure fitness, nutrition, body-fat distribution or overall health. For these reasons, the result should be treated as a screening value rather than a diagnosis or complete health assessment.
The fixed ranges shown by this calculator are intended for adults. BMI for children and teenagers is interpreted differently and should not be classified using these adult ranges.
Metric and imperial calculations are two ways of expressing the same height-and-weight relationship. If equivalent measurements are entered correctly, both methods should produce approximately the same BMI, allowing for normal rounding differences.
If you need to convert a weight measurement before using a calculator, ToolXone's Weight Converter can help convert between common weight units.
Use the result to understand which adult BMI range corresponds to the height and weight entered. Avoid interpreting the number as a complete description of health, fitness or body composition.
If an individual health assessment is needed, factors beyond BMI may need to be considered by an appropriately qualified healthcare professional.