Body Composition Calculator
Analyze your fat vs muscle ratio using the calculator below, or get an AI body composition estimate 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 2022 study of young football players in Children found BIA read about 10 percentage points below DEXA in men (9.3% vs 19.0%) and skinfolds about 6 points below (12.7%), so 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 gives you estimates of body fat %, muscle mass, lean mass, and fat mass, plus a physique score—all from a single photo.
- No body fat % input required
- AI estimates body fat from your photo and profile
- Physique score (Premium adds AI coaching)
- Track changes over time with photo history
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What the Research Says
Body Composition Tracking Benefits
A 2017 review in Advances in Nutrition on preserving muscle during weight loss found:
- Diet-induced weight loss also reduces muscle mass
- Resistance exercise and adequate protein help preserve muscle
Why Composition Beats Scale Weight
Research links what your weight is made of to health outcomes:
- Higher relative muscle mass is associated with lower insulin resistance and prediabetes (J Clin Endocrinol Metab, 2011)
- Abdominal obesity and excess visceral fat predict cardiovascular disease independently of BMI (American Heart Association, Circulation 2021)
Why Composition Matters
Track your body composition journey
Weight tells you how much. Composition tells you what. Track both to understand your real progress.
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