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Imperial BMI Calculator

BMI Calculator in lbs & feet

Calculate your BMI using pounds, feet, and inches.
The imperial formula: BMI = (lbs × 703) ÷ in²

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Imperial BMI Formula Explained

BMI = (lbs × 703) ÷ in²

Step 1: Convert height to total inches (feet × 12 + inches).
Example: 5'9" = (5 × 12) + 9 = 69 inches

Step 2: Square your height in inches.
Example: 69 × 69 = 4,761 in²

Step 3: Multiply weight (lbs) by 703, then divide by in².
Example: (154 × 703) ÷ 4,761 = 108,262 ÷ 4,761 = BMI 22.7 (Normal weight)

The factor 703 is the conversion constant that adjusts for pounds and inches to match the metric formula result.

Quick Reference

BMI at Common Weights for 5'9" (175cm)

Weight (lbs) Weight (kg) BMI Category
120 lbs 54 kg 17.7 Underweight
135 lbs 61 kg 19.9 Normal
150 lbs 68 kg 22.2 Normal
169 lbs 77 kg 25.0 Overweight
185 lbs 84 kg 27.4 Overweight
203 lbs 92 kg 30.0 Obese

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