Body Fat Calculator
Estimate your body fat percentage
About the Calculator
Body fat percentage gives a clearer picture of health than weight alone. This calculator uses the U.S. Navy method, which is a practical way to estimate body fat with simple measurements. It is not a medical diagnosis, but it helps you track progress and set realistic goals. Use it to compare changes over time, especially if you are strength training or working on body composition. Enter your measurements, select your unit system, and get a quick estimate. The key is consistency, so measure the same way each time to spot trends you can trust. Use the Body Fat Calculator to get a clear result you can act on right away.
Body Fat
14.6%
Fitness
Fat Mass
25.8 lb
Lean Mass
150.2 lb
The Formula
How to Calculate Manually
- 1
Measure your neck circumference at its narrowest point.
- 2
Measure your waist at the navel (relaxed, not sucked in).
- 3
Women: also measure hips at the widest point.
- 4
Measure height in centimeters.
- 5
Apply the Navy body fat formula.
Examples
Male with 40cm neck, 85cm waist, 180cm height
Approximately 18% body fat
Female with 35cm neck, 75cm waist, 95cm hips, 165cm height
Approximately 24% body fat
💡 Tips
- •Essential fat is 2-5% for men, 10-13% for women.
- •Athletes typically have 6-13% (men) or 14-20% (women).
- •Measure at the same time of day for consistency.
- •Body fat scales can vary widely in accuracy.
🎉 Fun Facts
- •Essential fat is non-negotiable: men need a minimum of 2-5% body fat to survive (for organs, bone marrow, nervous system), while women need 10-13% due to reproductive functions; going below this causes organ failure and death.
- •The body fat measurement chaos: the most accurate method (DEXA scan) costs $100-200 and uses X-rays, while bioelectrical impedance scales can be off by 8-10%, meaning you could be 18% or 28% body fat and both readings are "valid."
- •1 pound of fat vs muscle volume: one pound of fat takes up approximately 18% more space than one pound of muscle; which is why someone can lose fat and gain muscle, weigh the exact same on the scale, but drop 2-3 clothing sizes.
- •Visceral fat is the silent killer: you can have a "healthy" 20% body fat but if it is mostly visceral fat (around organs) rather than subcutaneous (under skin), your risk of heart disease, diabetes, and death is 5-10x higher than someone with 30% subcutaneous fat.
- •The gender fat gap: at the same body fat percentage, women appear leaner than men because they store fat in breasts and hips (subcutaneous) while men store it in the belly (visceral); a woman at 25% looks athletic while a man at 25% appears overweight.