Body Fat Calculator

Calculate your body fat percentage using the US Navy method. Enter your waist, neck, and height measurements to get an accurate body composition estimate.

Enter Your Measurements

Weight(lbs)

Waist Circumference(inches)

Neck Circumference(inches)

Height(inches)

Results

Body Fat Percentage

12.9

Body Fat Mass

23.2

lbs

Lean Body Mass

156.8

lbs

Formula

Body Fat % = (495 / Body Density) - 450. Body Density = 1.0324 - 0.19077 × log10(waist-neck) + 0.15456 × log10(height)

How to Use This Calculator

How to Use

1
Measure waist circumference at the level of your navel.
2
Measure neck circumference just below the larynx (Adam's apple).
3
Measure height accurately.
4
Your body fat percentage is calculated using the US Navy method.

Frequently Asked Questions

How is body fat percentage different from BMI?

Body fat percentage measures actual fat mass, while BMI is a general weight-to-height ratio. Body fat percentage is more accurate for assessing fitness, especially for muscular individuals.

What is a healthy body fat percentage?

For men, 10-20% is considered fit, 20-25% is average, 25%+ is overweight. For women, 18-25% is fit, 25-32% is average, 32%+ is overweight. Standards vary by age and fitness level.

How do I measure body fat accurately?

The Navy method using measurements is convenient and reasonably accurate. For highest accuracy, use DEXA scans, underwater weighing, or bioelectrical impedance tests.

In-Depth Guides

📖

BMI Guide: What Is a Healthy Weight? BMI Chart & Calculator

Understand BMI, what your score means, limitations of BMI, healthy weight ranges by height, and what to do if your BMI is outside the healthy range.

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About This Calculator

This calculator uses the formula: Body Fat % = (495 / Body Density) - 450. Body Density = 1.0324 - 0.19077 × log10(waist-neck) + 0.15456 × log10(height). All calculations follow industry-standard methods. Results are estimates — always verify with a licensed professional for structural or code-compliant work.

Built and maintained by the CalcSmart team. Last updated March 2026.

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