Fat-free mass index (FFMI)
Fat-free mass = weight × (1 − body fat percentage / 100); FFMI = fat-free mass / height², with height in metres. For men: normalized FFMI = FFMI + 6.3 × (1.8 − height), following the Kouri (1995) abstract.
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Calculation
Result
- Normalized FFMI
- 21.8 kg/m²
- Baseline FFMI
- 21.8 kg/m²
- Lean Body Mass (LBM)
- 70.5 kg
- Absolute Fat Mass
- 11.5 kg
Fat-free mass = weight × (1 − body fat percentage / 100); FFMI = fat-free mass / height², with height in metres. For men: normalized FFMI = FFMI + 6.3 × (1.8 − height), following the Kouri (1995) abstract. The original study included men. Normalization is not calculated for women. The value depends on body fat estimation accuracy; it does not diagnose steroid use, establish a genetic limit or define a universal health category.
Without height normalization
The original study included men. Normalization is not calculated for women. The value depends on body fat estimation accuracy; it does not diagnose steroid use, establish a genetic limit or define a universal health category.
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How it is calculated
Fat-free mass = weight × (1 − body fat percentage / 100); FFMI = fat-free mass / height², with height in metres. For men: normalized FFMI = FFMI + 6.3 × (1.8 − height), following the Kouri (1995) abstract.
Formula
Fat-free mass = weight × (1 − body fat percentage / 100); FFMI = fat-free mass / height², with height in metres. For men: normalized FFMI = FFMI + 6.3 × (1.8 − height), following the Kouri (1995) abstract.
Limits of the method
The original study included men. Normalization is not calculated for women. The value depends on body fat estimation accuracy; it does not diagnose steroid use, establish a genetic limit or define a universal health category.
Sources of the method
This calculation is for reference only and is not medical advice, a diagnosis or a prescription. If you have a medical condition, are pregnant, take medication or have any doubts, discuss the result with a physician or a qualified nutrition professional.
How to use the calculation
Enter the starting values
Fat-free mass = weight × (1 − body fat percentage / 100); FFMI = fat-free mass / height², with height in metres. For men: normalized FFMI = FFMI + 6.3 × (1.8 − height), following the Kouri (1995) abstract.
Adjust the parameters
Fat-free mass = weight × (1 − body fat percentage / 100); FFMI = fat-free mass / height², with height in metres. For men: normalized FFMI = FFMI + 6.3 × (1.8 − height), following the Kouri (1995) abstract.
Read the result
The original study included men. Normalization is not calculated for women. The value depends on body fat estimation accuracy; it does not diagnose steroid use, establish a genetic limit or define a universal health category.
Frequently asked questions
What does the calculation show?
Fat-free mass = weight × (1 − body fat percentage / 100); FFMI = fat-free mass / height², with height in metres. For men: normalized FFMI = FFMI + 6.3 × (1.8 − height), following the Kouri (1995) abstract.
What limitations apply?
The original study included men. Normalization is not calculated for women. The value depends on body fat estimation accuracy; it does not diagnose steroid use, establish a genetic limit or define a universal health category.
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What next
Formula breakdowns, biomarker reference ranges and nutrition articles with cited sources are in the NutriFit knowledge base.
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