📏Body Fat Calculator

Estimate body fat percentage using the US Navy method.

Gender

Waist (cm)

Neck (cm)

Height (cm)

About Body Fat Calculator

This body fat calculator uses the US Navy circumference method to estimate your body fat percentage from simple measurements — neck, waist, and hips — without expensive equipment. Body fat percentage is a far more meaningful health indicator than weight alone, as it distinguishes between lean mass and fat mass. Use this tool to track changes in body composition over time.

How to Use Body Fat Calculator

1
Take your measurements
Use a flexible tape measure to record your neck circumference, waist at its narrowest, and hips (women only) at the widest point.
2
Enter your details
Input your gender, height, and the three measurements into the calculator.
3
Track over time
Re-measure every 4–6 weeks under consistent conditions to monitor changes in body composition.

Common Use Cases

Tracking fat loss progress without relying on the scale
Assessing body composition before starting a fitness program
Monitoring lean mass retention during a calorie deficit
Setting a realistic body fat goal for athletic performance

Frequently Asked Questions

How accurate is the US Navy body fat method?

The US Navy method is considered accurate to within 3–4 percentage points for most people. It's less precise than DEXA scans or hydrostatic weighing, but far more practical and accessible for everyday tracking.

What is a healthy body fat percentage?

For men, essential fat is 2–5%, athletic range is 6–13%, fit is 14–17%, and average is 18–24%. For women, essential fat is 10–13%, athletic is 14–20%, fit is 21–24%, and average is 25–31%. Above 25% for men and 32% for women is generally considered obese.

How do I measure my waist accurately?

Measure your waist at the narrowest point (usually around the navel), not where your belt sits. Stand relaxed, exhale normally, and take the measurement before it bounces back. Avoid measuring after a large meal.