Smart Web Apps BMI Calculator
Category

BMI Calculator

Calculate your Body Mass Index (BMI) using metric or US units. Outputs include the formula and an interpretation category.

Enter height and weight, then click Calculate.
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Results
BMI
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Category (adult general)
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Formula
Metric: BMI = weight(kg) ÷ height(m)2
US: BMI = 703 × weight(lb) ÷ height(in)2

Tool description

BMI is a simple ratio of weight to height. It’s commonly used as a screening metric to categorize body weight (for adults), but it does not directly measure body fat or overall health.

How to use

  1. Select metric or US units.
  2. Enter height and weight.
  3. Click Calculate to see BMI and category.
  4. Use Copy results to paste into notes or a doctor’s message.

Why it’s useful

BMI helps quickly compare weight relative to height and can be used to track trends over time alongside other health metrics.

Use cases & interpretation

  • Personal tracking: calculate monthly BMI to see direction of change.
  • Screening: understand general categories (underweight/normal/overweight/obese) for adults.
  • Goal setting: pair BMI with waist circumference and activity for better context.

FAQs

Adult general categories: Underweight (< 18.5), Normal (18.5–24.9), Overweight (25.0–29.9), Obesity (≥ 30.0).

BMI is a screening metric. It can misclassify people with high muscle mass and may not reflect differences by age/sex/ethnicity.
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Disclaimer

This calculator is for informational purposes only and does not provide medical advice.