The body mass index (BMI), or Quetelet index, is a measure for human body shape based on an individual’s weight and height. It was devised between 1830 and 1850 by the Belgian polymath Adolphe Quetelet during the course of developing “social physics”. Body mass index is defined as the individual’s body mass divided by the square of their height. The formulae universally used in medicine produce a unit of measure of kg/m2. BMI can also be determined using a BMI chart, which displays BMI as a function of weight (horizontal axis) and height (vertical axis) using contour lines for different values of BMI or colors for different BMI categories.
† The factor for UK/US units is more precisely 703.06957964, but that level of precision is not meaningfulfor this calculation.
To work from stone and pounds first multiply the stone by 14 then add the pounds to give the whole mass in pounds; to work from feet and inches first multiply the feet by 12 then add the inches to give the whole height in inches.