Loading...
Calculate your Body Mass Index (BMI) using weight and height. Get your BMI category (underweight, normal, overweight, obese) and healthy weight range.
BMI is a numerical value derived from a person's weight and height (kg/m²) used to classify weight status and screen for potential health risks associated with being underweight, overweight, or obese.
Formula
BMI = weight (kg) ÷ height² (m)weight = body mass in kilograms
height² = height in meters, squared
Worked Example
Example: 75 kg person, 170 cm tall
Did you know? According to the World Health Organization, 39% of adults worldwide are overweight (BMI ≥ 25) and 13% are obese (BMI ≥ 30), making excess weight one of the leading preventable causes of disease globally.
Sources
Formula
BMI = weight (kg) ÷ height² (m²)BMI = Body Mass Index — a screening index, not a diagnostic tool
weight = Body mass in kilograms (kg)
height² = Height in metres, squared (m²)
Worked Example
BMI for 70 kg, 1.75 m tall
Did you know? BMI was developed by Belgian statistician Adolphe Quetelet in the 1830s as a population-level measure, not for individuals. The WHO BMI categories (underweight, normal, overweight, obese) were defined in 1995 and are now used by healthcare systems worldwide, despite known limitations for athletes and the elderly.
Sources
Calculate BMR using 3 validated formulas. See daily calorie needs by activity level.
Estimate BAC using the Widmark formula. Enter drinks, weight, and hours to gauge impairment.
Calculate body fat percentage using the US Navy method with simple body measurements.
Calculate daily calorie needs with BMR and TDEE. Get targets for weight loss, maintenance, or gain.
Calculate gestational age from your LMP. See due date, trimester, and milestones.
Find your 5 heart rate training zones using age or resting HR. Supports Karvonen method.