BMI Calculator
Work out your Body Mass Index and the weight range that suits your height.
Your healthy weight range: —
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Understanding Your BMI
Body Mass Index (BMI) compares your weight against your height to give a rough indication of whether you sit within a healthy weight range. Health professionals rely on it widely as a fast, first-pass screening measure.
The maths behind the number
The formula takes your weight in kilograms and divides it by your height in metres squared (kg/m²). Broadly, a figure between 18.5 and 24.9 counts as a healthy weight, 25 to 29.9 falls into the overweight category, and 30 or above is classed as obese.
What BMI can't tell you
A BMI figure is a guide rather than a diagnosis. Muscle mass, body composition, age and ethnicity all sit outside the calculation — which is why very muscular people can score as "overweight" while carrying little body fat. Use your number as a starting point, and get tailored advice from a professional.