BODY FAT
PERCENTAGE
CALCULATOR
Estimate your body fat percentage using the US Navy Method. This proven formula uses simple body measurements to provide an accurate assessment of your body composition.
// YOUR MEASUREMENTS
Measure without shoes
Measure at the narrowest point below Adam's apple
Men: at navel level. Women: at narrowest point
Measure at the widest point of your hips
// YOUR BODY COMPOSITION
ESTIMATED BODY FAT
18.5%
LEAN MASS
147
lbs
FAT MASS
33
lbs
BODY FAT CATEGORIES
Key insight: Your body fat percentage falls within the fitness range. This level supports athletic performance while maintaining essential body functions.
// BODY_FAT_SCIENCE
UNDERSTANDING BODY FAT PERCENTAGE
Body fat percentage is a key indicator of health and fitness that measures the proportion of your body weight that consists of fat tissue. Unlike BMI, body fat percentage distinguishes between fat mass and lean mass (muscle, bone, water, organs).
THE US NAVY METHOD
The US Navy Method is a well-validated circumference-based formula developed by the US Navy for assessing body composition. It uses height and circumference measurements at specific body sites to estimate body fat percentage with reasonable accuracy.
Men: 495 / (1.0324 - 0.19077 * log10(waist - neck) + 0.15456 * log10(height)) - 450
Women: 495 / (1.29579 - 0.35004 * log10(waist + hip - neck) + 0.22100 * log10(height)) - 450
BODY FAT CATEGORY RANGES
| CATEGORY | MEN | WOMEN |
|---|---|---|
| Essential Fat | 2-5% | 10-13% |
| Athletes | 6-13% | 14-20% |
| Fitness | 14-17% | 21-24% |
| Average | 18-24% | 25-31% |
| Obese | 25%+ | 32%+ |
WHY BODY FAT MATTERS
- Health risks: Excess body fat, especially visceral fat, is associated with increased risk of heart disease, diabetes, and other conditions
- Athletic performance: Lower body fat (within healthy ranges) can improve power-to-weight ratio and endurance
- Hormonal health: Body fat affects hormone production, including testosterone and estrogen
- Essential functions: Some body fat is necessary for organ protection, insulation, and nutrient absorption
MEASUREMENT TIPS FOR ACCURACY
- Consistency: Measure at the same time of day, preferably in the morning
- Neck: Measure at the narrowest point, just below the larynx (Adam's apple)
- Waist (men): Measure horizontally at navel level
- Waist (women): Measure at the narrowest point of the torso
- Hips (women): Measure at the widest point of the buttocks
- Posture: Stand relaxed with arms at sides, don't hold your breath or suck in
LIMITATIONS
While the Navy Method provides a reasonable estimate, it has limitations. Highly muscular individuals may get inaccurate readings. For the most accurate body fat measurement, consider DEXA scans, hydrostatic weighing, or air displacement plethysmography (Bod Pod).
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Disclaimer: This calculator provides estimates using the US Navy Method. Individual results may vary based on body type, muscle mass, and measurement technique. For precise body composition analysis, consult a healthcare professional or use clinical measurement methods like DEXA scanning.