How is BMI calculated?

BMI is calculated by dividing weight in kilograms by height in meters squared. The formula is BMI = weight (kg) / height (m)².

Can I calculate BMI using feet and inches?

Yes. This BMI calculator allows you to enter height in feet and inches and automatically converts the measurement to meters before calculating BMI.

BMI Calculator - Free Online BMI Calculator

Free Online Calculator

Calculate Your BMI

Enter your age, gender, weight and height. Choose the height unit that is easiest for you.

Age

years

Gender

Weight

Height Unit

Height

What Is BMI?

Body Mass Index, commonly called BMI, is a calculated measure of weight relative to height. It is commonly used as a screening measure for adults.

BMI does not directly measure body fat and should be considered together with other health information when assessing an individual's health.

BMI Formula

BMI = Weight (kg) ÷ Height (m)²

For example, if someone weighs 70 kg and is 1.75 meters tall:

70 ÷ (1.75 × 1.75) = 22.86

BMI Reference Calculation

Example: 70 kg and 175 cm

Step 1: Convert height from centimeters to meters.

175 cm ÷ 100 = 1.75 m

Step 2: Square the height.

1.75 × 1.75 = 3.0625

Step 3: Divide weight by squared height.

70 ÷ 3.0625 = 22.86

Result: BMI = 22.86

How to Use This BMI Calculator

Enter Your Age

Enter your age between 20 and 120 years. This calculator uses adult BMI categories.

Enter Your Weight

Enter your weight in kilograms.

Enter Your Height

Select centimeters, meters, or feet and inches and enter your height.

Adult BMI Reference Table

The following commonly used adult BMI categories apply to adults aged 20 and older.

BMI Range	Category
Below 18.5	Underweight
18.5 to less than 25	Healthy Weight
25 to less than 30	Overweight
30 or greater	Obesity

Is BMI a Diagnosis?

No. BMI is a screening measure rather than a diagnosis. A person's BMI should be considered together with other information such as medical history, health behaviors, physical examination findings and laboratory information.

BMI is interpreted differently for children and teenagers. This calculator is intended for adults aged 20 and older.

Frequently Asked Questions

BMI, or Body Mass Index, is a calculated measure of weight relative to height. It is commonly used as a screening measure for adults.

BMI is calculated by dividing weight in kilograms by height in meters squared.

BMI = weight (kg) ÷ height (m)²

Yes. Select "Feet & Inches" from the height unit menu. Enter your feet and inches and the calculator automatically converts the height before calculating BMI.

For adults, commonly used BMI categories are underweight below 18.5, healthy weight from 18.5 to less than 25, overweight from 25 to less than 30, and obesity at 30 or greater.

No. BMI is a screening measure and does not by itself diagnose a health condition. It should be considered together with other health information.

Important: This calculator provides an estimate of BMI for adults and is intended for informational purposes. BMI is a screening measure and is not a substitute for professional medical advice.

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