Body Composition Calculator
Get BMI, body fat percentage, waist-hip ratio, and lean mass — calculated from your measurements using the US Navy method.
What is body composition? Body composition is the ratio of fat, lean muscle, bone, and water in your body. Tracking BMI, body fat percentage, waist-hip ratio, and lean mass gives a more complete health picture than weight alone. The US Navy method estimates body fat from neck, waist, and hip measurements.
Your Measurements
Circumference measurements (for body fat %):
BMI
0
—
Body Fat
0%
US Navy
WHR
0
Waist/Hip
Lean Mass
0
lbs
BMI Category
BMI: 0Body Fat Range
0%US Navy formula. Most accurate when measurements are taken consistently — neck below larynx, waist at narrowest point (men: navel), hip at widest.
About These Metrics
- BMI = weight (kg) / height (m)². Useful population screen; doesn't distinguish fat from muscle.
- Body Fat % uses US Navy circumference method — within ±3% for most adults.
- WHR > 0.90 (men) or > 0.85 (women) suggests elevated cardiovascular risk.
- Lean Mass = total weight × (1 − body fat fraction).
Related Reading
-
Body Measurements for Fitness Progress: Step-by-Step Guide
Which body parts to measure, step-by-step technique, and how often to track for real results.
-
How to Calculate BMR and TDEE: Complete 2026 Guide
Use the Mifflin-St Jeor equation with step-by-step formulas, accuracy tips, and weight goal applications.
-
How to Set Realistic Health Goals in 2026
SMART framework, beginner examples, and a proven tracking system to make progress that lasts.
-
How to Track Macros for Beginners: A Complete Guide (2026)
Calculate macro targets, pick the right tools, and avoid the 6 most common beginner mistakes.
-
How to Improve Sleep Quality Naturally — 12 Tips (2026)
Science-backed sleep hygiene, breathing techniques, and recovery habits that support body composition.