Body Fat Calculator
Calculate your body fat percentage using the US Navy circumference method. Get accurate estimates of body fat, lean body mass, and fat mass. Perfect for tracking fitness progress and body composition goals.
How It Works
1. Select Gender and Units
Choose your gender (male/female) as the formulas differ, and select between imperial (inches, pounds) or metric (cm, kg) units.
2. Enter Weight and Height
Input your current body weight and height. Be as accurate as possible for the best results.
3. Measure Circumferences
Use a flexible measuring tape to measure neck and waist circumference. Women also measure hip circumference. Measure in the morning before eating for consistency.
4. View Your Body Composition
Get your body fat percentage, category (athlete, fitness, average, etc.), lean body mass, and fat mass instantly.
Examples
Example 1: Male - Fitness Category
Gender: Male Weight: 180 lbs Height: 5 feet 10 inches Neck: 15 inches Waist: 32 inches Results: Body Fat Percentage: 15.2% Category: Fitness Lean Body Mass: 152.6 lbs Fat Mass: 27.4 lbs This person is in the fitness range with healthy body composition.
Example 2: Female - Athletes Category
Gender: Female Weight: 140 lbs Height: 5 feet 6 inches Neck: 13 inches Waist: 27 inches Hip: 36 inches Results: Body Fat Percentage: 18.5% Category: Athletes Lean Body Mass: 114.1 lbs Fat Mass: 25.9 lbs This person is in the athletic range with excellent body composition.
Frequently Asked Questions
How accurate is the Navy method?
The US Navy circumference method is one of the most accurate non-clinical methods for estimating body fat percentage, with an error margin of approximately 3-4%. It is more accurate than BMI for assessing body composition because it accounts for body shape and muscle mass. However, methods like DEXA scans or hydrostatic weighing are more precise.
How do I measure correctly?
Use a flexible measuring tape (cloth or vinyl). For neck: measure below the larynx (Adam's apple). For waist (men): measure at navel level horizontally around abdomen. For waist (women): measure at narrowest point. For hips (women): measure at widest point. Stand naturally, do not hold your breath or suck in. Measure in the morning before eating for consistency.
What is a healthy body fat percentage?
For men: 10-20% is generally healthy, with athletes at 6-13% and fitness enthusiasts at 14-17%. For women: 18-28% is healthy, with athletes at 14-20% and fitness at 21-24%. Essential fat (needed for basic functions) is 2-5% for men and 10-13% for women. Body fat percentage varies with age, and older adults naturally have slightly higher percentages.
What is lean body mass?
Lean body mass (LBM) is everything in your body that is not fat - including muscle, bone, organs, and water. It represents the weight of your metabolically active tissue. Increasing lean body mass through strength training and proper nutrition improves metabolism, strength, and overall health.
How can I reduce body fat percentage?
Create a moderate caloric deficit through balanced nutrition and regular exercise. Combine strength training (to preserve/build muscle) with cardiovascular exercise. Aim to lose 1-2 pounds per week. Prioritize protein intake (0.7-1g per pound of body weight), get adequate sleep, manage stress, and stay hydrated. Focus on losing fat while maintaining lean mass for best results.