Know your real body fat percentage.
Weight alone doesn't tell the full story. Enter a few measurements and get an accurate body fat percentage estimate using the trusted Navy method, plus what it actually means.
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Everything about body composition, organized properly
From understanding your number to choosing the right approach for your goal.
Understanding Your Number
What body fat percentage ranges actually mean.
Measurement Methods
How different body fat methods compare.
Body Recomposition
Building muscle and losing fat together.
Diet Approaches
Keto vs. calorie deficit vs. macros.
Tracking Progress
Better ways to measure than the scale.
Exercise for Fat Loss
What actually moves the needle.
Free interactive tool
Body Fat Percentage Calculator
Enter your measurements and we'll calculate your estimated body fat percentage using the Navy method, plus what it means for your goal.
Your body fat estimate
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The essentials
Why the scale doesn't tell the whole story
Body weight alone is a poor indicator of health and fitness progress, since it doesn't distinguish between muscle, fat, and water weight.
Two people, same weight, different composition
Two people at the identical weight and height can look and perform completely differently depending on their body fat percentage and muscle mass.
Why the scale can be discouraging during recomposition
Someone building muscle while losing fat might see little scale movement despite meaningful, visible progress — a frustrating but common and completely normal pattern.
Better ways to track progress
Body measurements, progress photos, how clothes fit, and periodic body fat percentage checks give a much more complete picture than the scale alone.
Body fat calipers
An affordable, low-tech way to track body fat trends at home between formal measurements.
This content is for educational and informational purposes only and is not a substitute for personalized fitness or medical advice. Significant dietary or exercise changes are worth discussing with a doctor.
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Body composition tracking essentials
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The Body Composition Tracking Guide
A friendly, no-hype PDF that helps you understand and track your body fat percentage the right way.
- Healthy body fat ranges by gender and goal
- Measurement methods compared, honestly
- How body recomposition actually works
- Keto vs. calorie deficit: an honest comparison
- Better ways to track progress than the scale