Free Online BMI Calculator

Quickly calculate your Body Mass Index using metric or imperial units, see your weight category, healthy weight range, and understand how BMI applies to Asian adults.

BMI Calculator

BMI ranges are designed for adults. Children use BMI for age charts.
BMI ranges are the same for men and women, but body fat distribution differs.
Asian cut offs use a lower BMI for overweight and obesity, often used in Malaysia.
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kg
Standard WHO BMI categories for adults
BMI Weight category
Below 18.5 Underweight
18.5 - 24.9 Normal weight
25.0 - 29.9 Overweight
30.0 and above Obesity
Asian BMI categories (commonly used in Malaysia)
BMI Weight category
Below 18.5 Underweight
18.5 - 22.9 Normal weight
23.0 - 27.4 Overweight
27.5 and above Obesity

Frequently Asked Questions

What is BMI?

BMI (Body Mass Index) is a simple number that uses your height and weight to estimate whether your weight is in a broad healthy range. It is calculated as weight divided by height squared and is mainly used as a screening tool, not a diagnosis.

How is BMI calculated in metric and imperial units?

In metric units, BMI = weight (kg) ÷ [height (m)]². In imperial units, BMI = 703 × weight (lb) ÷ [height (in)]². This calculator uses the correct formula for each system and lets you switch between them easily.

What about Asian BMI categories?

For many Asian populations, including Malaysians, health authorities often use lower BMI cut offs because the risk of diabetes and heart disease can rise at lower BMI values compared to Western populations. You can switch between the standard WHO adult scale and the Asian cut offs using the selector above.

Is BMI accurate for everyone?

BMI is a general guide only. It does not account for muscle mass, bone structure, body fat distribution or certain medical conditions. Athletes and very muscular people may have a high BMI but a low body fat percentage. For older adults, BMI can underestimate body fat, and for children and teenagers, BMI must be interpreted using age specific charts. Always speak with a healthcare professional for a full assessment.