Tiny Toolkit

BMI Calculator — Body Mass Index, Metric & Imperial

Enter your weight and height in metric or imperial units to calculate your Body Mass Index and see which WHO weight category you fall into. The category table below the result highlights where your BMI sits among the standard ranges. BMI is a useful screening tool, though it doesn't account for muscle mass or body composition.

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Frequently Asked Questions

What does BMI measure?
BMI (Body Mass Index) estimates body fat based on weight and height. It is used as a screening tool to identify weight categories that may lead to health problems.
What are the BMI categories?
Underweight: below 18.5. Normal weight: 18.5–24.9. Overweight: 25–29.9. Obese: 30 and above. These categories apply to adults aged 18 and over.
Is BMI an accurate measure of health?
BMI does not measure body fat percentage directly and does not account for muscle mass, bone density, age, or sex. Athletes may have a high BMI despite low body fat. Use it as one indicator among many.

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