Get an accurate body fat percentage estimate using the US Navy method — a reliable field technique used by military fitness programs worldwide. All you need is a tape measure.
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Evidence-based strategies for body recomposition.
Consuming 1.6–2.2g protein per kg body weight while in a caloric deficit preserves muscle mass during fat loss. This is the most critical dietary lever for improving body composition.
Resistance training 3–4x per week stimulates muscle protein synthesis and increases resting metabolic rate. Even at the same body weight, more muscle means lower body fat percentage.
Sleep deprivation shifts weight loss from fat to muscle. In one study, dieters who slept 8.5 hours lost 55% fat vs. 25% fat for those who slept 5.5 hours on identical diets.
The US Navy circumference method estimates body density from simple tape measurements, then converts to body fat percentage using the Siri equation. For men, it requires waist and neck measurements. For women, it adds hip circumference to account for different fat distribution patterns. It was developed as a field-expedient alternative to immersion weighing and DEXA scanning.
Research shows it correlates well with DEXA (the gold standard) with typical errors of 3–4 percentage points. While not perfectly precise, it's repeatable and practical — making it ideal for tracking trends over time.
Body fat measurement explained.
For men: 6–13% athletic, 14–17% fitness, 18–25% acceptable. For women: 14–20% athletic, 21–24% fitness, 25–31% acceptable. Below essential fat ranges (<5% men, <13% women) risks organ damage.
The US Navy method is accurate within 3–4% compared to DEXA scan results for most people. It's less accurate for very muscular or very obese individuals. Use it to track trends rather than as an absolute measurement.
Use a flexible tape measure. Measure consistently: same time of day, after exhaling normally. Don't pull the tape tight — it should rest gently against the skin. Take 2–3 readings and average them for accuracy.
A realistic rate is 0.5–1% body fat reduction per month when following a proper protocol. Noticeable changes in body composition typically become visible after 6–12 weeks of consistent caloric deficit plus resistance training.
Body fat percentage is a more accurate health indicator because it distinguishes muscle from fat. A 90kg athlete with 12% body fat is far healthier than a 90kg sedentary person with 30% body fat, even if their BMI is identical.
Get the full picture of your body composition.
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