SuperCalc

BMI Calculator (Imperial)

Enter your weight in pounds and height in feet and inches to get your BMI instantly. The calculator converts to metric behind the scenes and gives you your BMI category, a color-coded gauge, healthy weight range (in both lbs and kg), and BMI Prime value.

BMI Calculator

Enter your height and weight to calculate your Body Mass Index.

Height
ft
in
lbs

BMI Categories

WHO classification of Body Mass Index ranges.

CategoryBMI Range
Underweight
< 18.5
Normal
18.5 – 24.9
Overweight
25 – 29.9
Obese I
30 – 34.9
Obese II
35 – 39.9
Obese III
40+

Frequently Asked Questions

What is the BMI formula in imperial units?
BMI = (weight in lbs / (height in inches)^2) x 703. For example, a person weighing 154 lbs and standing 5'9" (69 inches): BMI = (154 / 69^2) x 703 = (154 / 4761) x 703 = 22.7.
Why multiply by 703?
The factor 703 converts from pounds-per-square-inch to kilograms-per-square-meter, aligning the imperial formula with the original metric definition. Without it, the raw number would be meaningless against the standard BMI categories.
Is BMI the same regardless of the unit system?
Yes. Whether you input metric or imperial, the resulting BMI value is identical. The calculator handles the conversion internally. A BMI of 22.5 means the same thing whether you entered kg/cm or lbs/ft+in.

Medical disclaimer: BMI is a screening tool, not a medical diagnosis. It does not measure body fat directly and does not account for muscle mass, bone density, age, sex, or ethnicity. Consult a healthcare provider for personalized health advice.

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