FFMI Calculator

What is the FFMI Calculator – Fat-Free Mass Index?

The FFMI Calculator (Fat-Free Mass Index) measures muscularity in relation to height, with fat mass removed. It is a better measure for assessing muscle mass in athletes and bodybuilders compared to BMI.

The calculator is free and works in the browser without registration. This site offers over 200 calculators.

Calculation Principle

FFMI = FFM (kg) ÷ height² (m²). Normalized FFMI = FFMI + 6.1 × (1.8 − height_m).

Enter your information in the calculator fields – the result updates immediately. You can try different values to compare scenarios.

Practical Example

80 kg, body fat % 15, 180 cm → FFM = 68 kg → FFMI = 68 ÷ 3.24 = 20.99. Normal for a male athlete.

This example illustrates a typical situation. Enter your own data to get a personal result.

Who is the calculator suitable for?

The calculator serves individuals, entrepreneurs, students, and professionals. All calculators on this site are free and no registration is required.

The results are indicative – official decisions are always made based on calculations by professionals.

Tips and Notes

• Improve your awareness of body composition by combining FFMI with tracking body fat percentage and weight.
• Men: FFMI 18–20 normal, 20–22 good, 22–25 excellent training result.
• Women: FFMI values are naturally lower due to hormonal differences.