Body fat percentage measures the proportion of total body weight that is fat mass. Unlike BMI, it reveals composition quality, making it invaluable for fitness, health optimization, and tracking meaningful progress beyond scale weight.
Our calculator uses U.S. Navy circumference method and BMI-based approximation, outputting median estimates and lean body mass. Circumference methods are practical, affordable, and reliable when consistent. Track recomposition, assess fitness, or optimize health markers with actionable body composition context.
Males 10-24%, Females 18-31% for general health. Athletic ranges lower. Context matters—age, gender, genetics influence targets.
Body fat separates muscle from fat. Gain weight while losing fat through recomposition. Scale weight alone misses improvement.
Generally within 3-5 percentage points with proper technique. Consistency matters more than precision for trends.
Every 2-4 weeks using same method and time. Daily fluctuations from hydration obscure real trends.
Total weight minus fat mass. Includes muscle, bone, organs. Higher LBM correlates with metabolism and strength.
Yes (recomposition). Beginners with progressive resistance, protein, mild deficit can improve composition without weight rising.
1.6-2.2 g/kg body weight preserves/builds muscle during deficit.
Poor sleep alters hunger hormones, increases cravings. Quality sleep supports fat loss and muscle retention.
Extremely low impairs hormones and immunity. Essential fat (10-13% males, 18-20% females) necessary for health.
Hydration, glycogen, digestion affect readings. Standardize: same time, morning fasted, several days averaged.