Body Fat Calculator Guide
Understanding the US Navy method and body composition
What is Body Fat Percentage?
Body fat percentage is the proportion of your total body weight that consists of fat tissue. Unlike BMI, it distinguishes between fat mass and lean mass (muscle, bone, water, organs).
Formula:
Body Fat % = (Fat Mass ÷ Total Weight) × 100
The US Navy Method
Developed by the U.S. Navy for assessing military personnel fitness. It uses simple body measurements to estimate body fat with reasonable accuracy.
For Men
Measurements needed: Height, Neck, Waist (at navel)
For Women
Measurements needed: Height, Neck, Waist, Hips
How to Measure Accurately
Neck
Measure just below the Adam's apple. Keep tape level.
Waist
Men: at navel level. Women: narrowest point between ribs and hips.
Hips (Women only)
Widest point of the buttocks. Keep tape parallel to floor.
Pro Tips:
- • Measure in the morning before eating
- • Take 3 measurements and use the average
- • Keep tape snug but not tight
- • Stand relaxed, don't flex or suck in
Body Fat Categories
Men
Women
Limitations of This Method
- ⚠️ Estimates can vary by 3-4% from actual body fat
- ⚠️ Less accurate for very lean or very overweight individuals
- ⚠️ Doesn't account for fat distribution
- ⚠️ Measurement technique affects accuracy
For more precise measurements, consider DEXA scans, hydrostatic weighing, or professional calipers.
Reducing Body Fat
Nutrition
- • Caloric deficit (TDEE - 500)
- • High protein (preserve muscle)
- • Whole foods focus
Exercise
- • Resistance training
- • HIIT or steady cardio
- • Increase daily movement