BMI Calculator

Body Mass Index (BMI) is a measurement that estimates body fat based on your height and weight. It's calculated by dividing your weight in kilograms by the square of your height in metres.

Healthcare professionals use BMI as a screening tool to identify whether an adult may be at increased risk of health conditions associated with being underweight, overweight, or obese. It's one of several indicators used alongside other assessments to get a fuller picture of your health.

BMI is a useful starting point, but it doesn't tell the whole story. There are several important factors it doesn't account for:

• Muscle mass - BMI can't distinguish between muscle and fat. Athletes and people with higher muscle mass may show a higher BMI despite having low body fat.
• Age - BMI is designed for adults and becomes less reliable for people over 65, as body composition changes with age.
• Ethnicity - Health risks associated with BMI vary across ethnic groups. People of South Asian, Chinese, Black African, or African-Caribbean backgrounds may face higher risks at lower BMI thresholds.
• Pregnancy - BMI should be based on pre-pregnancy weight for pregnant individuals.
• Body fat distribution - BMI doesn't account for where fat is stored. Excess fat around the waist carries greater health risks than fat stored in other areas.