Body Fat Calculator
Estimate your body fat percentage using the US Navy method
What is the US Navy Body Fat Method?
The US Navy method estimates body fat percentage using circumference measurements rather than skinfold calipers or expensive DEXA scans. It was developed for military fitness assessments and has been validated against hydrostatic weighing, making it one of the most accurate free methods available.
For men the formula uses waist and neck measurements alongside height. For women it adds hip measurement to account for the different fat distribution patterns between sexes. Measurements should be taken at the same time of day, ideally in the morning, for the most consistent results.
Body Fat Percentage Categories
For men, essential fat is 2 to 5 percent, athletic range is 6 to 13 percent, fitness range is 14 to 17 percent, acceptable is 18 to 24 percent, and obese is 25 percent and above. For women, essential fat is 10 to 13 percent, athletic is 14 to 20 percent, fitness is 21 to 24 percent, acceptable is 25 to 31 percent, and obese is 32 percent and above.
How to Take Accurate Measurements
Waist should be measured horizontally at the level of the navel, not at the narrowest point. Neck should be measured just below the larynx with the tape slightly sloping downward at the front. For women, hips should be measured at the widest point. Keep the tape snug but not compressing the skin, and take each measurement twice and average the results.
Body Fat Calculator — Frequently Asked Questions
What is a healthy body fat percentage?
Healthy body fat ranges differ by sex. For men, 10–20% is generally considered fit and healthy, with athletes typically at 6–13%. For women, 18–28% is the healthy range, with female athletes typically at 14–20%. These ranges are based on American Council on Exercise (ACE) classifications.
What is the US Navy body fat method?
The US Navy circumference method estimates body fat using simple tape measurements — waist and neck for men, and waist, hip and neck for women. It was developed and validated by the US Navy and requires no specialist equipment.
How accurate is the US Navy body fat formula?
The US Navy method has an accuracy of approximately ±3–4% compared to DEXA scans, making it a reliable estimate for most people. It is less accurate for very muscular individuals or those with unusual fat distribution patterns.