BMI chart: what is my body mass index? 

How to calculate BMI

Your BMI (body mass index) is your weight divided by your height multiplied by itself.

You can download or print our BMI chart (pictured below) to work it out:

1. Use weighing scales to measure your weight in kilograms or stones. Find this number on the top of the chart.
2. Use a tape measure to work out your height in centimetres or feet and inches. Find this number on the left side of the chart.
3. Draw or trace a line down from your weight and across from your height to see which part of the chart they meet in. This will tell you your BMI.

What is a healthy BMI?

Your BMI will be classed as 1 of 4 categories:

If your BMI is classed as overweight, you have a higher risk of developing cardiovascular disease and having a life-threatening event, such as a heart attack or stroke.

If your BMI is obese, you’re at an even higher risk.

If your BMI is underweight, you may have a greater risk of health problems too. Speak to your GP if your BMI is classed as overweight, obese or underweight.

How does ethnic background affect BMI?

People from different ethnic groups store body fat in different ways.

This means people from an Asian, Black African, African-Caribbean or Middle Eastern ethnic background may have a higher risk of health problems at a lower BMI.

You can download or print our BMI chart (pictured below) to work out your risk.

However, the categories of ethnic backgrounds are broad as there’s less research on people from mixed backgrounds. That's why it may help to look at other measures alongside BMI too.

Is BMI accurate?

BMI alone does not determine your risk of cardiovascular disease. This is because it does not measure where fat is in the body and cannot tell the difference between fat and muscle. BMI is inaccurate for:

• pregnant people
• people who have a lot of muscle
• people who have conditions that affect their height
• children and teenagers.

Excess fat around the waist can also increase your risk of cardiovascular disease, even if your BMI is healthy. Working out your waist-to-height ratio may be a more accurate tool and it’s suitable for all ages and ethnicities.

• Find out how to measure your weight-to-height ratio.

BMI tracker

Download or print our BMI tracker to see how your BMI changes over time. You can monitor your BMI by taking measurements and writing them down in this diary every 3 months.

Try to weigh yourself at the same time of day, under the same conditions and on the same set of reliable scales.

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