BMI Calculator

Underweight (below 18.5) this may be a sign that you are not eating enough or unwell. If you are underweight you can speak to your GP for support.

Healthy weight (between 18.5 and 24.9) this suggests you are in a healthy weight range for your height. Aim to continue making healthy choices with your diet and lifestyle to maintain this.

Overweight (between 25 and 29.9) & Obese (30 or over) - if your BMI is in the overweight or obese category it is possible to work your way towards a healthy weight by improving your diet and levels of physical activity. Remember healthy weight loss is achieved by making small, gradual changes consistently.

Black, Asian, and other minority ethnic groups have a higher risk of developing some long-term (chronic) conditions e.g., type 2 diabetes. These adults with a BMI of 23 or more are at increased risk.

• BMI cannot determine the difference between excess fat, muscle or bone in the body and relies on total body weight
• Adult BMI does not consider age or gender
• This means that:
  • Individuals who are very muscular could be classed as ‘overweight’ or ‘obese’ even though their % of excess fat is low
  • Adults of an older age may lose muscle overtime and may calculate as a healthy weight even though they have a high % of excess fat
• If you are pregnant your BMI result will be affected. Pre-pregnancy weight should be used when calculating BMI.

Although limitations are identified, BMI is a useful and convenient tool to assess your weight, monitor progress and consider your overall health.

In addition to BMI, measuring your waist circumference can be used to check for excess fat being carried around your stomach, which can raise your risk of heart disease, stroke and type 2 diabetes.

It is possible to be a healthy weight and carry too much excess fat which may still increase your risk of the above conditions.

To calculate your waist circumference:

1. Find the bottom of your ribs and the top of your hips.
2. Wrap a tape measure around your waist midway between these points.
3. Breathe out naturally before taking the measurement with the tape measure.
4. Use the table below to understand your measurement