Your Measurements
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BMI Categories (CDC Standard)
- Underweight: BMI below 18.5
- Normal weight: BMI 18.5–24.9
- Overweight: BMI 25–29.9
- Obesity Class I: BMI 30–34.9
- Obesity Class II: BMI 35–39.9
- Obesity Class III: BMI 40 or higher
BMI Formula
Imperial: BMI = (weight in pounds / height in inches²) × 703
Metric: BMI = weight in kg / (height in meters)²
BMI Limitations
BMI is a useful screening tool but has well-known limitations. It does not account for muscle mass, bone density, or body fat distribution. Athletes and very muscular individuals often have high BMIs despite low body fat. BMI is also less accurate for people over 65. For a more complete picture, combine BMI with waist circumference, body fat percentage, and clinical assessment.