Health & Fitness
FFMI Calculator - Calculate fat-free mass index
Calculate fat-free mass index for athletes.
Formulas and edge cases are reviewed against authoritative references before publication. For methodology, editorial standards, or corrections, use the links below.
Frequently asked questions
What is FFMI?
Fat-Free Mass Index measures muscularity independent of body fat, useful for athletes and bodybuilders.
What is a good FFMI?
Average male: 18-20, Athletic: 20-22, Elite natural: 22-25, Above 25 suggests PED use.
Why normalize FFMI?
Normalization adjusts for height differences, allowing fair comparison between people.
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About this tool
This FFMI Calculator turns your inputs into practical results. Provide Height, Weight, and Below Average to calculate FFMI and Lean Mass.
Adjust values to compare scenarios and see how sensitive the result is. The calculation uses the numbers as entered, so double-check units and expect small differences from rounding in the displayed totals.