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This is not medical advice. Physique Calculator is an educational estimation tool, not a diagnostic device, and not a substitute for professional medical, nutritional, or fitness guidance.
Every number this Website produces — body fat percentage, FFMI, normalized FFMI, lean mass, fat mass, BMI, estimated calorie and protein targets — is an estimate generated from published formulas and the measurements you enter. It is intended to help you understand general body-composition concepts, not to diagnose, treat, or assess any medical condition.
Every calculation on this site is only as accurate as the measurements behind it. Body fat percentage in particular — whether entered directly or estimated from circumference measurements — is typically the largest source of uncertainty, and it feeds directly into lean mass, fat mass, FFMI, and calorie estimates. Small measurement errors can noticeably shift the results. See the Methodology page for a full explanation of where uncertainty comes from.
Fat-free mass includes muscle, but also bone, organs, body water, and connective tissue — FFMI is not a direct measurement of muscularity. The reference bands shown alongside your FFMI result (Below Average / Average / Above Average / High) are general descriptive reference points, not a peer-reviewed population percentile table, a medical threshold, or a judgment about how a physique was achieved. We deliberately do not use FFMI to speculate about anabolic steroid use or "natural genetic potential," and we'd encourage you to treat any calculator or source that does so with skepticism.
Before starting a new diet, exercise program, or making significant changes based on anything calculated on this Website, consult a doctor, registered dietitian, or qualified fitness professional — particularly if you have an existing health condition, are pregnant, are under 18, or have a history of disordered eating.
The Exercise Library provides general technique information and links to third-party video demonstrations. Exercise carries an inherent risk of injury. Use proper form, appropriate weight, and your own judgment, and stop immediately if something feels wrong. We are not responsible for injuries resulting from exercises described or linked on this Website.
Using this Website does not create a doctor-patient, dietitian-client, coach-client, or any other professional relationship between you and Physique Calculator or its maintainer(s).
If anything on this page is unclear, reach out via our Contact page. See also our Terms of Use and Privacy Policy.