Calculators/bmi calculator

BMI Calculator

Calculate your body mass index (BMI) from height and weight and see the standard adult BMI category. BMI is a screening tool, not a diagnosis. Athletic build, body composition, pregnancy, and health conditions can affect how useful BMI is for an individual.

Inputs
lb

Results

BMI
24.39
CategoryHealthy weight
Healthy weight range128.9173.6 lb
Adult BMI categories are shown for reference.

How to use it

  • Choose US or metric units.
  • Enter your height and weight.
  • Review your BMI value and the adult category.
  • Optionally check the estimated “healthy weight” range for your height.

Key formulas

BMI (metric)
BMI = kg / m²
BMI (US)
BMI = 703 × lb / in²

FAQ

For adults, BMI is commonly grouped as underweight (<18.5), healthy weight (18.5–24.9), overweight (25–29.9), and obesity (30+), with obesity sometimes split into classes.

Not always. BMI doesn’t measure body fat directly and can misclassify very muscular people, older adults, or people with unusual body composition. Use it as a rough screening tool.

Children and teens are typically evaluated using BMI-for-age percentiles, not the adult categories. This calculator uses adult categories only.

It’s the weight range that corresponds to the BMI interval 18.5–24.9 for a given height. It’s an estimate and doesn’t account for body composition.

BMI can be used as a general reference, but pregnancy changes weight and body composition. Talk to a healthcare professional for individualized guidance.

Sources

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Disclaimer

Informational estimates only. BMI is a screening metric and not medical advice. For health concerns, consult a qualified healthcare professional.

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