Health & Body Calculators
Free health calculators for Army body fat (tape test) and macro nutrients (IIFYM). Instant results, no signup needed.
Understanding your body composition and nutritional needs is the foundation of any fitness or health goal. These calculators use standardized, research-backed formulas — the same ones used by the US Army and registered dietitians — to give you numbers you can actually act on.
What these tools cover
The Army body fat calculator uses the US Army tape-test method: neck, waist, and hip circumference measurements to estimate body fat percentage for both men and women, and checks the result against the Army's branch-specific retention standards by age group. No calipers or DEXA scan required. The macro calculator estimates your daily caloric needs using the Mifflin-St Jeor BMR equation adjusted for activity level, then splits calories into protein, carbohydrate, and fat targets based on your goal (maintain, cut, or bulk).
Health disclaimer
Body fat estimates from circumference measurements carry a margin of error of ±3–4% compared to laboratory methods. Macro targets are starting points — individual metabolism, medical conditions, and training history all affect what actually works for you. These tools are for general informational use; consult a qualified healthcare provider or registered dietitian before making significant dietary changes.
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