Body composition

Compare published estimates of body size, body fat, lean mass and surface area.

• BMI Calculator

  Calculate your body mass index from your height and weight, and see which WHO category it falls in.

• Body Fat Calculator

  Estimate your body fat percentage from tape measurements using the US Navy circumference method.

• Lean Body Mass Calculator

  Estimate lean body mass from height and weight using the Boer, James and Hume equations, shown side by side.

• Ideal Weight Calculator

  See the WHO healthy weight range for your height, alongside what the Devine, Robinson, Miller and Hamwi formulas report.

• Healthy Weight Range Calculator

  Find the weight range that corresponds to a BMI of 18.5 to 24.9 at your height, and how far any current weight sits from it.

• Waist-to-Hip Ratio Calculator

  Divide your waist by your hip measurement and compare the result with the WHO thresholds for fat distribution.

• Body Surface Area Calculator

  Calculate body surface area with the Mosteller, Du Bois, Haycock, Gehan-George and Boyd equations, and see how far apart they are.

• Army Body Fat Calculator

  Estimate body fat with the US Army’s one-site tape equation, from weight and the abdomen measured at the navel.

• Height Predictor Calculator

  Estimate a child’s target adult height range from both parents’ heights, using the mid-parental method of Tanner and colleagues.

• FFMI Calculator

  Work out your fat-free mass index from weight, height and a body fat estimate, and the height-normalised figure from Kouri and colleagues.