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BMI Calculator

Calculate your Body Mass Index, see your weight category and discover your ideal healthy weight range.

cm
kg

Your BMI

—

Underweight
<18.5 Normal
18.5–25 Overweight
25–30 Obese
>30
— BMI
— Category
— Ideal weight
— Weight to lose/gain

Healthy Weight Range for Your Height

BMI Categories

Underweight
Below 18.5
Normal weight
18.5 – 24.9
Overweight
25.0 – 29.9
Obesity Class I
30.0 – 34.9
Obesity Class II
35.0 – 39.9
Obesity Class III
40.0 and above

Note: BMI is a screening tool, not a diagnostic measure. Consult a healthcare provider for medical advice.

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How to Use BMI Calculator

To calculate your BMI, enter your height and weight using either metric (cm and kg) or imperial (feet, inches, and pounds) units. The calculator instantly computes your Body Mass Index and displays which WHO category it falls into: Underweight, Normal weight, Overweight, or Obese.

The result panel also shows your healthy weight range for your height, giving you a concrete target range to aim for. Remember that BMI is a population-level screening tool and does not account for muscle mass, age, or body composition — always consult a healthcare professional for personalised medical advice.

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Frequently Asked Questions

What is BMI and how is it calculated? expand_more

BMI (Body Mass Index) is a simple measure calculated by dividing weight in kilograms by height in metres squared: BMI = kg / m². It provides a rough estimate of body fat based on height and weight.

What are the standard BMI categories? expand_more

According to WHO guidelines: under 18.5 is Underweight, 18.5–24.9 is Normal weight, 25.0–29.9 is Overweight, and 30.0 or above is Obese.

Does BMI apply equally to men and women? expand_more

The same BMI scale is used for both men and women aged 18 and over. However, women typically have more body fat than men at the same BMI, which is why BMI is considered a screening tool rather than a definitive health measure.

Is BMI accurate for athletes or very muscular people? expand_more

BMI can overestimate body fat in athletes and muscular individuals because muscle is denser than fat. A person with high muscle mass may have a high BMI while actually having low body fat.

What BMI is considered healthy? expand_more

A BMI between 18.5 and 24.9 is considered the healthy (normal) weight range for adults. This range is associated with the lowest risk of weight-related health problems in population studies.

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