Fitness

Fat-Free Mass Index (FFMI) Calculator

Calculate your muscle mass relative to height, adjusting for body fat percentage.

Fat-Free Mass Index (FFMI) Calculator

Calculate your muscle mass relative to height, adjusting for body fat percentage.

This calculator is for informational purposes only and does not constitute medical advice. Consult a healthcare professional for personalised guidance.

How This is Calculated

FFMI = fat-free mass (kg) ÷ height² (m²). Fat-free mass = weight × (1 − body fat % / 100). Normalized FFMI = FFMI + 6.1 × (1.8 − height in m). Developed by Kouri et al. (1995). An FFMI of 25+ is near the upper natural limit for men; values above 26 may suggest anabolic assistance.

Disclaimer: This tool provides estimates for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Marcus Mueller
Created by Marcus Mueller Software Developer & Tech Specialist

Seasoned software developer and tech specialist, building tools that make people's life easier.

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