How to calculate BMI
Body mass index is weight in kilograms divided by height in metres squared. In imperial units it is weight in pounds divided by height in inches squared, multiplied by 703.
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The formula
BMI = kg ÷ m². Imperial: BMI = lb ÷ in² × 703.
Step by step
- Measure height and weight in one consistent set of units.
- Square the height.
- Divide the weight by the squared height.
- Multiply by 703 if you used pounds and inches.
Worked example
70 kg at 1.75 m
- Height squared = 1.75 × 1.75 = 3.0625
- BMI = 70 ÷ 3.0625
BMI is 22.9 to one decimal place.
Common questions
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Cite this page
APA
Free Calculator. (n.d.). How to calculate BMI. https://freecalculator.tech/guides/how-to-calculate-bmi
MLA
"How to calculate BMI." Free Calculator, https://freecalculator.tech/guides/how-to-calculate-bmi.
Link
How to calculate BMI — Free Calculator, https://freecalculator.tech/guides/how-to-calculate-bmi