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BMI Calculator

Calculate Body Mass Index with metric and imperial units.

⚖️ What is BMI Calculator?

BMI (Body Mass Index) is an international standard metric that measures body fat based on height and weight ratio. It is calculated by dividing weight (kg) by the square of height (m), and is the obesity assessment standard recommended by the WHO. This calculator computes your BMI from entered height and weight, showing your normal weight range and ideal weight. A visual BMI range chart helps you understand your current health status at a glance.

📊 WHO BMI Classification

CategoryBMI RangeHealth Risk
UnderweightBelow 18.5Nutritional deficiency risk
Normal18.5 - 24.9Healthy weight range
Overweight25 - 29.9Lifestyle changes recommended
Obese Class I30 - 34.9Increased metabolic syndrome risk
Obese Class II+35 and aboveHigh cardiovascular disease risk

💡 BMI Limitations and Complementary Metrics

  • Muscle mass not reflected: Athletes may have high BMI but be healthy (check body fat percentage)
  • Fat distribution: Abdominal fat is more dangerous; measure waist circumference
  • Age/gender differences: Same BMI means different things for elderly vs young adults
  • Not applicable for pregnancy: BMI standards do not apply during pregnancy

Frequently Asked Questions

Why are Asian BMI standards different from Western ones?

Asians have higher body fat percentage and more visceral fat at the same BMI, increasing cardiovascular disease risk. Therefore, 23+ is classified as overweight, lower than the WHO standard of 25+.

My BMI is normal but I have belly fat. Why?

BMI only measures overall weight ratio and cannot detect "skinny fat." Check your waist circumference (men over 40 inches, women over 35 inches) or body fat percentage as well.

Can children and teenagers use these standards?

No. During growth periods, BMI percentiles by age are used. Adult BMI standards only apply to those 18 years and older.

What is BMI Calculator?

Calculate your Body Mass Index (BMI) using height and weight in metric (kg/cm) or imperial (lb/ft) units. See if you are underweight, normal, overweight, or obese.

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