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Calculate your BMI

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Your Body Mass Index or BMI is a good way for you to check if you’re a healthy weight. For adults BMI is used to measure if you’re a healthy weight for your height meaning the calculation takes into account that all people are different shapes and sizes.

BMI formula

You can also work out your BMI by using the formula below. To calculate your Body Mass Index, you'll need to know your weight in kilos and your height in metres.

Step one: Multiply your height in metres by itself, eg 1.7 x 1.7= 2.89

Step two: Divide your weight in Kilos by this figure, e.g 80 ÷ 2.89 = 27.7

Step three: For this example 27.7 is your BMI

BMI chart

A Body Mass Index chart is a helpful tool for visualising the range associated with each BMI category

BMI table

What does yout BMI score mean?

Below 18.5

A score this low means that you may be underweight. There are a number of possible reasons for this and your GP can help you achieve a healthy weight. You can also read our weight gain article to find out what you can eat to gain weight healthily.

18.5 - 24.9

This is a healthy BMI range, and it shows that you're a healthy weight for your height. Make sure that you are eating your 5-portions of fruit and vegetables a day and drink plenty of water.

25 or more

Your BMI is above the ideal range and this score means you may be overweight. This means that you're heavier than is healthy for someone of your height. Carrying excess weight can put you at increased risk of heart disease, stroke and type 2 diabetes. To find out how you can healthily lose weight, read our weight loss article here.

30 or more

A BMI above 30 is classified as obese. Being obese puts you at a raised risk of health problems such as heart disease, stroke and type 2 diabetes. Losing weight will help to improve your health and well-being. Read our top 12 tips for weight loss today.

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