Body Composition Calculator
Analyze your fat vs muscle ratio using the calculator below, or get instant AI-powered body composition analysis from a photo.
The Limits of Body Composition Estimates
Body composition calculators that rely on body fat percentage input are only as accurate as your body fat estimate. A systematic review published in PMC found that common estimation methods like BIA scales and calipers have error margins of ±3-8%—meaning your calculated lean mass, muscle mass, and other metrics could be significantly off.
Body Composition Calculator
Your Measurements
Use our body fat calculator if you don't know your percentage
Estimates based on body fat percentage
Get Complete Body Analysis
More than just numbers
PhysiqueAI's AI analysis gives you body fat %, lean mass, muscle distribution, and a physique score—all from a single photo.
- No body fat % input required
- AI estimates body fat directly from photo
- Detailed muscle distribution analysis
- Physique score with actionable feedback
- Track changes over time with photo history
No credit card required
What the Research Says
Body Composition Tracking Benefits
A study in the Journal of Sports Sciences found that tracking body composition rather than weight alone provides more meaningful feedback for athletes and fitness enthusiasts:
- Weight can stay the same while body composition improves dramatically
- Lean mass preservation is critical during fat loss phases
- Muscle-to-fat ratio better predicts metabolic health than BMI
Why Composition Beats Scale Weight
Research from the American Journal of Clinical Nutrition demonstrates that body composition is a better predictor of health outcomes:
- Higher muscle mass correlates with better insulin sensitivity
- Excess fat mass increases cardiovascular risk regardless of BMI
- Body recomposition improves health markers even without weight change
Why Composition Matters
Track your body composition journey
Weight tells you how much. Composition tells you what. Track both to understand your real progress.
No credit card required • 3 free scans/month