Body Fat Calculator
Estimate your body fat percentage using the U.S. Navy formula with simple tape measurements.
This calculator auto-updates when values change.
Estimated Body Fat
Body fat percentage
18.8%
Average range
Method
U.S. Navy body fat formula
The formula compares your height with circumference measurements. It is a practical estimate, not a lab measurement.
About This Body Fat Calculator
Body fat percentage gives a clearer picture of body composition than body weight alone. Weight can change due to hydration, muscle gain, and other factors, while body fat percentage estimates the proportion of your body made up of fat tissue.
This calculator uses the U.S. Navy Body Fat formula. It requires only a tape measure, making it an accessible way to estimate body composition at home without expensive equipment.
How to Use This Calculator
- 1
Select gender and units
Choose the formula and unit system that applies to your measurements.
- 2
Measure height, neck, and waist
Use a flexible tape measure and keep it level.
- 3
Add hip measurement if needed
The female U.S. Navy formula also uses hip circumference.
- 4
Review the estimate
Use the body fat percentage and category as a general guide.
Frequently Asked Questions
How accurate is the Navy Body Fat formula?v
It is a practical estimate, but less accurate than clinical methods such as DEXA scans.
Why do men and women have different formulas?v
The formulas differ because fat distribution patterns are generally different between men and women.
What is an ideal body fat percentage?v
It depends on age, sex, fitness level, and health context.
When is the best time to measure?v
Measure under similar conditions each time, ideally when relaxed and not immediately after exercise.
Why is my body fat percentage different from my BMI?v
BMI uses height and weight only. Body fat formulas use circumference measurements to estimate body composition.
How tight should I pull the measuring tape?v
Keep the tape snug but not compressed into the skin.