Body Fat Calculator
Estimate your body fat percentage using the U.S. Navy method.
What is Body Fat Percentage?
Your body fat percentage is simply the total mass of fat divided by your total body mass, multiplied by 100. It includes both essential body fat (which is necessary to maintain life and reproductive functions) and storage body fat (the fat that accumulates as energy reserves over your chest, stomach, hips, and thighs).
Understanding your true body fat percentage is infinitely more useful than simply tracking your weight on a scale, because the scale cannot differentiate between 5 pounds of lost fat and 5 pounds of lost muscle.
How The U.S. Navy Method Works
Our calculator uses the official method prescribed by the United States Navy to track the fitness of its personnel. Because water displacement tests (DEXA scans) are expensive and impractical, the military devised a highly effective formula relying entirely on a standard tape measure.
For Men: The calculation compares the circumference of the neck to the circumference of the waist (measured exactly at the navel). Men tend to store excess body fat predominantly around their midsections.
For Women: The calculation adds hip circumference to the equation, comparing the neck against the sum of the waist and the widest point of the hips. Due to evolutionary genetics, women naturally store healthy fat reserves around the hips and thighs.
Note on Accuracy: While not as precise as an MRI or DEXA scan, the tape measure method is widely considered accurate enough (margin of error ±3-4%) to track long term progress effectively.
Healthy Body Fat Chart
Because women require more essential fat for reproductive health and hormonal balance, female and male body fat charts scale differently.
| Category | Men | Women |
|---|---|---|
| Essential Fat | 2% - 5% | 10% - 13% |
| Athletes | 6% - 13% | 14% - 20% |
| Fitness / Average | 14% - 24% | 21% - 31% |
| Obese | 25% or higher | 32% or higher |
How to Measure Correctly
- Neck: Measure just below the larynx (Adam's apple). Do not flex the neck or crane it forward. Keep the tape flat but not excessively tight.
- Waist: For Men: Measure exactly level with the navel (belly button). Do not suck your stomach in.
For Women: Measure at the narrowest point of the waist, usually halfway between the bottom rib and the hips. - Hips (Women only): Measure at the maximum, widest circumference of the hips and buttocks while standing with feet together.