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BMI Calculator
Calculate Body Mass Index. Know if underweight, normal, overweight or obese.
⭐ Used by 12,450 people

The BMI (Body Mass Index) Calculator measures your body fat based on height and weight. BMI is the most widely used tool by doctors and health professionals to assess healthy weight ranges.

BMI Formula

BMI = Weight (kg) / Height² (m)
Example: Weight 70kg, Height 1.70m
BMI = 70 / (1.70 × 1.70) = 24.2 → Normal ✅

BMI Categories

BMI RangeCategoryHealth Risk
Below 18.5UnderweightModerate
18.5 – 24.9Normal WeightLow ✅
25.0 – 29.9OverweightModerate
30.0 – 34.9Obese Class IHigh
35.0 – 39.9Obese Class IIVery High
40+Obese Class IIIExtremely High

Limitations of BMI

  • BMI doesn't distinguish between muscle and fat
  • Athletes may show high BMI despite being very healthy
  • BMI ranges differ slightly for Asian populations
  • Always consult a doctor for health assessment
📖 Complete Guide
Formulas, examples, tips & FAQs
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Frequently Asked Questions

What is a healthy BMI range?

For most adults, a BMI between 18.5 and 24.9 is considered healthy. Below 18.5 is underweight, 25 to 29.9 is overweight, and 30 or above is classed as obese.

Is BMI accurate for everyone?

BMI is a useful general guide but it does not distinguish between muscle and fat. Athletes with high muscle mass may show a high BMI while being very healthy, so it should be used alongside other health measures.

How is BMI calculated?

BMI is your weight in kilograms divided by your height in metres squared. For example, a person weighing 70 kg and 1.75 m tall has a BMI of about 22.9.