Health Suite

Body Fat Calculator

Estimate your body fat percentage using the highly regarded U.S. Navy Method. Calculate your fat mass and lean mass instantly.

Age

Height (ft)

Height (in)

Weight (lbs)

Neck (in)

Waist (in)

Enter your measurements to see your estimated body fat percentage.

Understanding Body Fat Percentage

Body fat percentage is a superior metric of health compared to BMI because it differentiates between fat mass and lean body mass (muscle, bone, water). Our calculator uses the globally recognized U.S. Navy Method to estimate your body fat percentage using simple tape measurements.

The U.S. Navy Method Logic

The algorithm calculates body density by analyzing the circumference of specific body parts relative to your height. Since fat is distributed differently across genders, the formulas differ:

Men:
% Fat = 86.010 × log10(abdomen - neck) - 70.041 × log10(height) + 36.76

Women:
% Fat = 163.205 × log10(waist + hip - neck) - 97.684 × log10(height) - 78.387

FAQ

The U.S. Navy Method is considered one of the most accurate methods for estimating body fat percentage without using specialized equipment like DEXA scans or calipers. It uses simple tape measurements to provide a solid estimate within 3-4% accuracy for most people.

Use a flexible measuring tape. Measure your neck just below the larynx, perfectly horizontal. Measure your waist at the narrowest point (or at the navel for men). For women, measure the hips at the widest circumference.

Healthy ranges vary by age and gender. Generally, for men, 10-20% is considered healthy/fitness, and for women, 20-30% is considered healthy/fitness. Lower ranges exist for athletes.

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