Body Fat Calculator (Navy Method)

Estimate body fat percentage using the US Navy circumference method. See body fat category and lean body mass.

By Konstantin Iakovlev · Updated April 2026 · Source: CDC

Sex
in
lbs
in
in

Body Fat Percentage

17.5%

Fitness

Fat Mass

31.5 lbs

Lean Body Mass

148.5 lbs

Male Body Fat Categories

Essential Fat2-5%
Athletes6-13%
Fitness14-17%
Average18-24%
Obese25%+

Calculated using the U.S. Navy body fat estimation method. This is an estimate and may not be accurate for all body types. Consult a healthcare provider for precise measurements.

Use the Body Fat Calculator (Navy Method) above to calculate your results. Enter your values and see instant results — all calculations run in your browser.

Disclaimer: This calculator is for informational purposes only and does not constitute tax, financial, or legal advice. Results are estimates based on the information you provide and current rates. Always consult a qualified tax professional or financial advisor for advice specific to your situation.

How It Works

Estimating body fat percentage through the US Navy circumference method gives you a quick, equipment-light read on body composition using nothing more than a tape measure. The number carries real health meaning: research through 2026 continues to associate higher body fat with greater rates of cardiovascular disease, type 2 diabetes, and certain cancers. It also tracks fitness progress more honestly than scale weight alone, since two people at the same weight can carry very different amounts of fat.

Behind the estimate, the Navy method feeds your measurements into a body-density calculation and then translates that density into a fat percentage using the Siri formula. Men supply neck and waist circumference; women add hip circumference to those two. The figures are combined on a logarithmic scale to arrive at the final estimate.

Accuracy depends on technique, so take each measurement the same way every time, ideally with the same person measuring and at a consistent hour of the day. Skip readings right after hard exercise or a large meal, both of which can briefly distort your dimensions. The method is dependable for everyday tracking, but it remains an estimate and will not match the precision of lab-based tools such as a DEXA scan.

Example: Calculating Body Fat for a 35-year-old Male

  1. 1 A 35-year-old male, 6 feet tall and weighing 190 lbs, takes his measurements. His neck circumference is 16 inches and his waist circumference is 34 inches.
  2. 2 Using the Navy Method formulas, the calculator first determines the circumference value: Waist - Neck = 34 - 16 = 18 inches. Then, it applies the logarithmic formula for men: 86.010 * log10(Waist - Neck) - 70.041 * log10(Height) + 36.76. Assuming a height of 72 inches, the calculation proceeds to estimate body density and then body fat percentage.
  3. 3 Based on these inputs, the calculator estimates a body fat percentage of 18.5%. This places him in the 'Fitness' category according to typical body fat percentage charts for men, which range from 14-20%. His lean body mass is calculated as 190 lbs * (1 - 0.185) = 154.95 lbs.
  4. 4 This result indicates a healthy body fat range for an adult male, suggesting a good balance of muscle and fat. Regular monitoring of these metrics can help him maintain his fitness goals and identify any significant changes in his body composition over time. If his goal was to be in the 'Athletic' category (6-13%), he would aim to reduce his body fat by approximately 5.5%.

Source: CDC · Last updated: April 2026

Frequently Asked Questions

What is a healthy body fat percentage?
For men: 10-20% is considered fit to healthy, 21-24% is acceptable, and above 25% is obese. For women: 18-28% is fit to healthy, 29-31% is acceptable, and above 32% is obese. Athletes are typically lower.
How does the Navy body fat method work?
The US Navy method estimates body fat using circumference measurements. For men, it uses neck and waist measurements. For women, it uses neck, waist, and hip measurements, combined with height in a logarithmic formula.
Is body fat percentage more useful than BMI?
Yes, body fat percentage is generally more informative because it measures actual fat tissue. BMI cannot distinguish between muscle and fat, so a muscular person may have a "high" BMI but low body fat. Body fat percentage is a better indicator of health risk.

You might also need

HSA Calculator 2026 — Contribution Limits & Triple Tax Savings

Calculate HSA tax savings, investment growth, and projected balance at retirement. See the triple tax advantage in action. Based on 2026 IRS contribution limits.

BMI Calculator — Body Mass Index, Category & Healthy Range

Calculate your Body Mass Index (BMI) from height and weight. See your BMI category, healthy weight range, and what it means. Free, instant results with chart.

Calorie Calculator (TDEE)

Calculate daily calories for maintenance, weight loss, or gain using the Mifflin-St Jeor equation and your activity level.