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BMI Calculator

BMI stands for Body Mass Index. It gives you an idea of whether you're underweight, overweight or an ideal weight for your height.

Enter your height and weight

It’s useful to know because when your weight increases (or decreases) outside of the ideal range, health risks may also increase.


How accurate is the BMI?

The BMI is a useful measurement for most people over 18. But there are limitations to this system. For instance:

  • Adults with a very athletic build (eg, professional athletes) could show as overweight. This is because muscle weighs more than fat and the BMI does not take this into account.
  • If you’re pregnant, the BMI does not apply. You should seek advice from your doctor or midwife on what a healthy weight is.
  • See your doctor if you require a more precise reading.


What do the numbers mean?

  • Underweight = <18.5
  • Normal weight = 18.5–24.9
  • Overweight = 25–29.9
  • Obesity = BMI of 30 or greater

Find out about losing weight

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