Body Composition Calculator
Calculate your lean mass, fat mass, and see how your body fat percentage compares to athlete, fitness, and average ranges.
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Body Composition Breakdown
Body composition breaks your total weight into fat mass and lean mass (muscle, bone, water, organs).
Formulas:
Fat Mass = Weight × (Body Fat % / 100)
Lean Mass = Weight − Fat Mass
In metric (kg):
Fat Mass (kg) = Weight (kg) × Body Fat % / 100
In imperial (lbs):
Fat Mass (lbs) = Weight (lbs) × Body Fat % / 100
Body fat percentage ranges (men):
- Essential fat: 2–5%
- Athlete: 6–13%
- Fitness: 14–17%
- Average: 18–24%
- Obese: 25%+
Body fat percentage ranges (women):
- Essential fat: 10–13%
- Athlete: 14–20%
- Fitness: 21–24%
- Average: 25–31%
- Obese: 32%+