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Body Fat Percentage Calculator

Calculate your body fat % using the US Navy method or BMI-based formula. Find fat mass, lean mass, and fitness category. Supports metric and imperial units.

Last Updated: May 2026
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17.7%

Body Fat %

13.3 kg

Fat Mass

61.7 kg

Lean Mass

Average

Based on male reference ranges

EssentialAthletesFitnessAverageObese

Body Fat % vs BMI: Which Matters More?

BMI (Body Mass Index) measures weight relative to height and cannot differentiate between muscle and fat. A bodybuilder may have a "obese" BMI while having 10% body fat. Body fat percentage is a far more accurate indicator of health and fitness level. Use both together for a complete picture.

How to Reduce Body Fat

The most effective approach combines a moderate calorie deficit (250–500 kcal/day below TDEE), adequate protein intake (0.7–1g per lb bodyweight), and resistance training 2–4 times per week to preserve lean mass. Cardio accelerates fat loss but is not strictly required.

Frequently Asked Questions

What is the US Navy body fat calculation method?

The US Navy method estimates body fat percentage using circumference measurements. For men, it requires waist and neck circumference plus height. For women, it also requires hip circumference. The formula uses a logarithmic calculation that has been validated across a broad population range and is used by military branches for fitness assessments.

What is a healthy body fat percentage?

Healthy ranges differ by sex. For men: Essential fat 2–5%, Athletes 6–13%, Fitness 14–17%, Average 18–24%, Obese 25%+. For women: Essential fat 10–13%, Athletes 14–20%, Fitness 21–24%, Average 25–31%, Obese 32%+. Note that some body fat is essential for hormone function and organ protection.

Which body fat method is more accurate — Navy or BMI?

The Navy circumference method is more accurate than the BMI method for most people, because BMI does not distinguish between muscle and fat. However, the gold standard methods are DEXA scan (X-ray), hydrostatic weighing, and Bod Pod. Navy method accuracy is typically within ±3-4% of DEXA results for most people.

How do I measure my waist circumference correctly?

For the Navy method, measure your waist at the narrowest point (typically just above the belly button), not at the hip. Keep the tape parallel to the floor and measure after a normal exhale. For women, measure hip circumference at the widest point. Neck measurement is taken just below the Adam's apple.

Can I lose body fat without losing weight?

Yes — this is called body recomposition. When you build muscle while losing fat, your total weight may stay the same or even increase while your body fat percentage decreases. This is common for beginners who start resistance training. Tracking body fat % and lean mass over time is more informative than scale weight alone.

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