BMI Explained

Maintained by Prince Yadav — Founder & Lead Developer, Ganitra Calculator. This guide is written and maintained as part of Ganitra Calculator’s first-party educational content.

What is BMI?

BMI is a screening measure based on weight relative to height. It does not directly measure body fat or distinguish muscle from fat.

The formula

BMI = weight in kilograms divided by height in meters squared.

Using the result

Use BMI as a general screening number rather than a diagnosis. Individual health decisions should consider other measurements and professional advice where appropriate.

BMI categories

Adult BMI categories are commonly used as screening ranges, but category boundaries do not capture every difference in body composition or health status.

What BMI leaves out

BMI does not directly measure body-fat distribution, muscle mass, fitness, medical history, or many other factors that affect health.

Worked example

If someone weighs 70 kg and is 1.75 m tall, BMI is 70 ÷ 1.75², or about 22.9. The number is a screening value rather than a diagnosis.

When context matters

Age, pregnancy, muscle mass, medical conditions, and other circumstances can affect how useful BMI is for an individual.

Using the calculator responsibly

Use BMI as one data point. If you are concerned about health, nutrition, or symptoms, use appropriate professional guidance rather than relying on the calculator alone.

Related Calculators

Use the Calculator

Take the concepts from this guide and test your own assumptions in the calculator.