Skip to main content

Health Advice - Measuring

Your Body Mass Index or BMI is calculated by multiplying your height in metres by itself and then dividing your weight in kg by the height-x-height figure.
e.g for a height of 1.64 m (5ft 4”) and a weight of 60 kg (approx 9 and a half stone) the calculation is:
60 divided by (1.64 x 1.64) , therefore it is 60 divided by 2.6896.
In this instance the BMI is 22.3

Calculate your BMI

Follow the link for an automatic BMI calculator

What does your BMI mean?

  • BMI 18-24.9: Healthy

  • BMI 25-29.9: Overweight

  • BMI 30-34.9: Obese

  • BMI 35-39.9: Seriously Obese

  • BMI > 40: Morbidly Obese

Measure your waist

Use the table below to see whether your current weight and size is likely to put you at risk of damage to your general health.


Assessing risks to your health from overweight and obesity

BMI classification

Waist circumference



Very High


No increased risk

Increased risk

High risk


Increased risk

High risk

Very high risk

For men, waist circumference of less than 94cm (37 inches) is low, 94 – 102 cm (37 to 40 inches) is high and more than 102 cm (40 inches) is very high.

For women, waist circumference of less than 80 cm (32 inches) is low, 80 – 88 cm (32 to 35) inches is high and more than 88 cm (35 inches) is very high