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⚖️ BMI Calculator

Calculate your Body Mass Index

ft
in
lbs
Your BMI 23.0 Normal Weight
16 18.5 25 30 40
Under Normal Over Obese

Healthy Weight Range for Your Height

124 - 167 lbs

BMI Categories

Underweight Below 18.5
Normal Weight 18.5 – 24.9
Overweight 25 – 29.9
Obesity Class I 30 – 34.9
Obesity Class II 35 – 39.9
Obesity Class III 40 and above

Frequently Asked Questions

What is BMI?

BMI (Body Mass Index) is a measure of body fat based on height and weight. It's calculated by dividing weight in kilograms by height in meters squared (kg/m²).

BMI is used as a screening tool to identify possible weight problems in adults, but it's not a diagnostic measure.

How is BMI calculated?

Metric: BMI = weight (kg) ÷ height (m)²

Imperial: BMI = (weight in lbs × 703) ÷ (height in inches)²

Example: 160 lbs, 5'10" (70 inches):
(160 × 703) ÷ (70 × 70) = 112,480 ÷ 4,900 = 23.0

Is BMI accurate for everyone?

BMI has limitations:

  • Athletes: Muscle weighs more than fat, so fit people may have a "high" BMI
  • Elderly: May have more fat and less muscle at the same BMI
  • Body type: Doesn't account for where fat is stored

BMI is a screening tool. For a complete health assessment, consult a healthcare provider.

What's a healthy BMI?

For most adults, a healthy BMI is 18.5 to 24.9. However:

  • Optimal BMI may vary by age and ethnicity
  • Athletes often have higher BMI due to muscle
  • Body fat percentage is often a better measure
Does BMI apply to children?

For children and teens (ages 2-19), BMI is calculated the same way but interpreted differently. It's compared to growth charts that account for age and sex, resulting in a BMI percentile.

This calculator is designed for adults (20+). For children, consult a pediatrician.