Body Fat Calculator
U.S. Navy Method
Measurements
Below the larynx
At navel level
For mass calculations
Body Fat Categories (Men)
Calculated using the U.S. Navy Method. This is an estimate based on circumference measurements and may differ from DEXA scans or hydrostatic weighing. Consult a professional for precise measurements.
How the Body Fat Calculator Works
This body fat calculator uses the U.S. Navy Method, a circumference-based formula developed by the Naval Health Research Center. Originally designed to assess fitness levels of Navy personnel, this method provides a reliable estimate of body fat percentage using simple tape measurements that you can take at home.
The U.S. Navy Body Fat Formula
The calculation uses logarithmic equations that account for the relationship between body circumferences and fat distribution. For men, the formula uses neck, waist, and height measurements. For women, hip circumference is added to improve accuracy, since women naturally store more fat in the hip and thigh region.
How to Take Accurate Measurements
- Neck: Measure just below the larynx (Adam's apple), keeping the tape level and not too tight
- Waist (Men): Measure at navel level, standing relaxed without sucking in your stomach
- Waist (Women): Measure at the narrowest point of your torso, typically just above the belly button
- Hips (Women): Measure at the widest point of your buttocks with feet together
Understanding Body Fat Categories
The American Council on Exercise (ACE) defines body fat categories based on health and athletic performance. Essential fat is the minimum required for basic physiological function—going below this level is dangerous. Athletes typically maintain lower body fat for performance, while the fitness range represents a healthy, sustainable level for active individuals.
Accuracy and Limitations
The Navy Method typically estimates body fat within 3-4% of more precise methods like DEXA scanning. However, accuracy can vary based on individual body composition. Highly muscular individuals may get inflated readings, while those with unusual fat distribution patterns may see less accurate results. For tracking progress over time, consistency in measurement technique matters more than absolute accuracy.