About BMI - Body Mass Index

Body Mass Index (BMI) is a measure of body fat based on height and weight that applies to adult men and women. It was developed by Belgian statistician Adolphe Quetelet in the 1830s and is now widely used as a screening tool to identify potential weight problems.

BMI provides a simple numeric measure of a person's thickness or thinness, allowing health professionals to discuss weight problems more objectively with their patients.

BMI is calculated using a simple formula:

Example Calculation

If you weigh 70 kg and are 1.75 m tall:

• BMI = 70 ÷ (1.75 × 1.75)
• BMI = 70 ÷ 3.0625
• BMI = 22.9

While BMI is a useful screening tool, it has several limitations:

Doesn't Account for Muscle Mass

BMI doesn't distinguish between muscle and fat. Athletes with high muscle mass may have a high BMI but low body fat percentage.

Age and Sex Differences

BMI doesn't account for age or sex differences in body composition. Women tend to have more body fat than men with the same BMI. This is why BMI chart by age and gender considerations are important for accurate health assessment. Our BMI calculator for adults provides general guidelines, but individual variations exist.

Ethnic Variations

Different ethnic groups may have different body compositions at the same BMI level. Some populations may be at higher risk for health problems at lower BMI values.

Doesn't Measure Body Fat Distribution

BMI doesn't indicate where body fat is located. Abdominal fat (visceral fat) is more dangerous than fat in other areas of the body.

BMI Calculator for Children

Our BMI calculator is designed for adults 18 and older. BMI calculator for children requires different interpretation using age and sex percentiles. Children's BMI changes significantly with age and development, so pediatric BMI charts are used instead of adult categories.