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About This Calculator
Body fat percentage reveals how much of your total weight is composed of fat tissue versus lean mass like muscle, bone, and organs. This calculator uses body measurements such as waist, neck, and hip circumference along with height to estimate your body fat percentage. It provides a more nuanced picture of body composition than weight alone, helping you set realistic fitness goals.
Quick Tips
- 1 Men under 15% and women under 25% body fat are generally considered fit.
- 2 Use calipers or DEXA scans for accuracy since scales and formulas have wide error margins.
- 3 Track body fat percentage instead of weight to see if you are losing fat vs. muscle.
Example Calculation
A 28-year-old male: waist 34", neck 15.5", height 71" (US Navy method).
Body fat: 16.8% | Category: Fitness | Fat mass: 30.2 lbs | Lean mass: 149.8 lbs
What is Body Fat Percentage?
Body fat percentage is the proportion of your total body weight that consists of fat tissue. It is a more meaningful health indicator than weight alone because it distinguishes between fat mass and lean mass (muscle, bone, water, organs). Healthy body fat ranges are typically 6-24% for men and 14-31% for women.
The US Navy Body Fat Method
The U.S. Navy method estimates body fat using circumference measurements of the neck, waist, and (for women) hips, along with height. It was developed for military fitness assessments and has been validated against more expensive methods like DEXA scans. While not as precise as laboratory methods, it provides a reliable estimate using only a tape measure.
Body Fat Categories
For men: essential fat is 2-5%, athletic is 6-13%, fit is 14-17%, average is 18-24%, and obese is 25% and above. For women: essential fat is 10-13%, athletic is 14-20%, fit is 21-24%, average is 25-31%, and obese is 32% and above. These ranges account for the biological differences in fat storage between sexes.
How to Reduce Body Fat
Reducing body fat requires a combination of caloric deficit, resistance training to preserve muscle mass, adequate protein intake (0.7-1g per pound of body weight), and consistent cardiovascular exercise. Aim to lose 0.5-1% of body fat per month for sustainable results. Crash diets often lead to muscle loss rather than fat loss.
Frequently Asked Questions
The US Navy method is accurate within about 3-4% of DEXA scan results for most people. It tends to be most accurate for individuals with average body compositions and may be less accurate for very lean or very obese individuals.
For men, 14-17% is considered fit and 18-24% is average. For women, 21-24% is fit and 25-31% is average. Essential fat minimums are 2-5% for men and 10-13% for women — going below these levels is dangerous.
Women naturally carry more essential body fat due to hormonal differences and reproductive biology. Fat stored in the breasts, hips, and thighs serves important roles in hormone production and reproductive health.
Body fat percentage provides more useful information than BMI because it measures actual fat levels rather than just weight relative to height. A muscular person may have a high BMI but low body fat, making body fat percentage the better health indicator.