FFMI Calculator

Across the literature, most trained natural men sit at an adjusted FFMI below 25 and most trained natural women below 23. These ceilings are statistical, not absolute — a small fraction of natural lifters with elite genetics can exceed them, but adjusted FFMI well above the threshold is widely considered a strong indicator of pharmacological assistance.

Yes, by a large margin. BMI lumps muscle and fat together, so a 90 kg lifter at 12% body fat reads "overweight" the same as a 90 kg sedentary person at 30% body fat. FFMI separates lean mass and gives a number that actually reflects training progress, which is exactly what you care about.

Yes. This calculator accepts either a direct body-fat percentage (from a DEXA, BIA scale or trained eye estimate) or U.S. Navy measurements (neck, waist, plus hip for women). Navy measurements typically read within 3% of DEXA for lean lifters and 5% for those above 25% body fat.

Raw FFMI systematically penalizes taller lifters and rewards shorter ones because it scales lean mass by height squared, which is too generous as height increases. The adjusted formula adds 6.3 × (1.8 − height in meters) to compensate, so a 1.65 m and a 1.95 m lifter with equivalent muscularity get comparable scores.

Beginners can typically gain 1–2 FFMI points in their first year of consistent training, then 0.5–1 point per year for the next 2–3 years, with progress slowing after that. If your adjusted FFMI is climbing more than 1 point per year past the 3-year mark of serious training, double-check your body-fat reading — gains often come from improved measurement accuracy, not new muscle.