Body Fat Calculator – Estimate Your Body Fat Percentage
Our body fat calculator uses the US Navy circumference method to estimate your body fat percentage quickly and accurately without specialized equipment. Simply enter your measurements to find out how much of your body weight is fat versus lean mass. Understanding your body fat percentage is a key indicator of overall health and fitness beyond just weight or BMI.
Enter your age in years.
Enter your height in centimeters.
Enter your current body weight in kilograms.
Measure around the narrowest part of your neck.
Measure at the narrowest point (for men) or at the navel level (for women).
Measure around the widest part of your hips. Required for female calculation.
Your results will appear here
How to Use This Calculator
1. Select your gender (male or female), as the formula differs between sexes. 2. Enter your age, height in centimeters, and body weight in kilograms. 3. Measure and enter your neck circumference at its narrowest point. 4. Measure and enter your waist circumference (at the narrowest point for men, or at navel level for women). 5. If you are female, also measure and enter your hip circumference at the widest point. 6. Click Calculate to instantly see your body fat percentage, fat mass, lean body mass, and your fitness category.
How Body Fat Percentage Is Calculated
This calculator uses the US Navy Method, one of the most widely used and validated circumference-based methods for estimating body fat percentage. It was developed by Hodgdon and Beckett in 1984 and uses simple body measurements to approximate the results you might get from more expensive methods like DEXA scans or hydrostatic weighing.
Formula for Men
For males, the formula is:
Body Fat % = 495 / (1.0324 − 0.19077 × log10(waist − neck) + 0.15456 × log10(height)) − 450
Formula for Women
For females, the hip measurement is also required:
Body Fat % = 495 / (1.29579 − 0.35004 × log10(waist + hip − neck) + 0.22100 × log10(height)) − 450
Body Fat Categories
Once your body fat percentage is calculated, it is classified into one of these standard fitness categories:
- Essential Fat: Men <6%, Women <14% — the minimum amount of fat needed for basic bodily functions.
- Athletic: Men 6–13%, Women 14–20% — typical of professional athletes and very active individuals.
- Fitness: Men 14–17%, Women 21–24% — associated with regular exercise and a healthy lifestyle.
- Average: Men 18–24%, Women 25–31% — the normal range for the general population.
- Obese: Men ≥25%, Women ≥32% — associated with increased health risks.
Fat Mass vs. Lean Body Mass
Your fat mass is the total weight of body fat you carry. Your lean body mass includes everything else — muscle, bone, water, and organs. Tracking both values is more informative than tracking total weight alone, especially when following a fitness or nutrition program.
Limitations of This Method
While the US Navy method is convenient and reasonably accurate for most people, it has some limitations. It may be less accurate for very muscular individuals, the elderly, or people with unusual body proportions. For clinical-grade accuracy, consider a DEXA scan or hydrostatic weighing.