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Body Fat Calculator

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32" waist, 16" neck, 70" height = approximately 18% body fat

Estimate your body fat percentage using the U.S. Navy circumference method. This calculator uses your height, waist, neck, and hip measurements (for women) to calculate body fat. Understanding your body composition helps you set realistic fitness goals and track progress beyond just weight.

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How We Calculate This

This calculator uses the U.S. Navy circumference method developed by Hodgdon and Beckett. For men: %BF = 86.010×log10(waist-neck) - 70.041×log10(height) + 36.76. For women: %BF = 163.205×log10(waist+hip-neck) - 97.684×log10(height) - 78.387.

Frequently Asked Questions

How accurate is the Navy body fat formula?

The U.S. Navy method is generally accurate within 3-4% of more precise methods like DEXA scans. It is most accurate for people with average body compositions.

What is a healthy body fat percentage?

For men, 10-20% is considered fit, with athletes often at 6-13%. For women, 18-28% is fit, with athletes at 14-20%. Essential fat is 2-5% for men and 10-13% for women.

How do I measure my waist correctly?

Measure your waist at navel level while standing relaxed. Do not suck in your stomach. The tape should be snug but not compressing the skin.

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