Body Fat Calculator
Educational overview of body composition measurement methods.
Guide: Body Fat Calculator
Body fat percentage can be estimated with skinfold calipers, bioelectrical impedance scales, or lab methods like DXA. Each has error bands. This page is educational: compare methods before trusting a single number. Body composition matters for metabolic health and athletic performance, but obsession over single-digit precision is rarely productive without a consistent measurement protocol.
Why cheap scales fluctuate
Hydration, meal timing, and calluses affect BIA readings. Track trends rather than single-day precision.
Menstrual cycle fluid shifts can also move impedance; some users weigh and measure only at the same cycle phase.
Skinfold and caliper technique
Trained testers measure multiple sites and sum skinfolds into body-density equations. DIY caliper use improves with practice videos and consistent pinch sites.
If skinfold totals rise while scale weight falls, you may be gaining muscle and losing fat—a win even if bathroom gadgets disagree.
Gold-standard trade-offs
DXA exposes you to minimal radiation but costs time and money. Underwater weighing and air displacement plethysmography exist in labs.
For most people, waist-to-height ratio plus strength benchmarks is enough between occasional lab checks.