Body Fat Calculator
Estimate body fat percentage, fat mass, lean body mass, and target weight using U.S. Navy circumference and BMI methods.
| Scenario | Profile | Body Fat Percentage |
|---|---|---|
Base Settings | Default physical measurements and inputs | 16.4% |
Conservative | 5% larger waist circumference (moderate body fat gain) | 19.6% |
Optimistic | 5% smaller waist and slightly larger neck (body fat reduction) | 12.4% |
Stress Test | 20% larger waist and smaller neck (extreme body fat gain) | 29.1% |
Uses the US Navy circumference method. General estimate only.
How to Use the Body Fat Calculator
Estimate your body fat percentage, fat mass, and lean muscle mass at home using scientifically validated algorithms. Choose between the U.S. Navy circumference method (widely used in military and fitness assessments) and the Deurenberg BMI body fat estimation method.
- Unit System: Bounded parameter in the mathematical model.
- Methodology: Bounded parameter in the mathematical model.
- Gender: Bounded parameter in the mathematical model.
- Age: Bounded parameter in the mathematical model.
- Height: Bounded parameter in the mathematical model.
- Total Body Weight: Bounded parameter in the mathematical model.
- Waist Circumference: Bounded parameter in the mathematical model.
- Neck Circumference: Bounded parameter in the mathematical model.
- Hip Circumference (women only): Bounded parameter in the mathematical model.
- Target Body Fat %: Bounded parameter in the mathematical model.
Body Fat Calculator Explained: Formula, Math, and Precedence
Determine Body Fat Percentage and analyze outcomes with step-by-step working.
Read Full Guide →How does the U.S. Navy body fat method work?
Developed by Hodgdon & Beckett at the Naval Health Research Center, this method calculates body fat percentage from circumference ratios (waist, neck, and hip relative to height). It serves as an accessible, high-accuracy alternative to hydrostatic weighing.
What is the difference between the Navy method and the BMI method?
The Navy method measures actual physical circumferences to differentiate between fat and muscle mass. The Deurenberg BMI method estimates fat based solely on age, gender, and total BMI, making it less specific for athletic individuals.
What body fat percentage is considered healthy?
According to the American Council on Exercise (ACE), healthy fitness ranges are 14–17% for men and 21–24% for women. Essential fat required for physiological survival is 2–5% for men and 10–13% for women.
Calculate Waist-to-Height Ratio (WHtR) to check abdominal fat distribution and metabolic health risk classification using Ashwell Shape Chart standards.
Waist-to-Hip Ratio CalculatorCalculate Waist-to-Hip Ratio (WHR) and evaluate cardiovascular and metabolic health risk categories based on WHO standards.
Lean Body Mass CalculatorCalculate Lean Body Mass (LBM), fat mass, and body composition ratios using Boer, James, and Hume formulas.
Body Surface Area CalculatorCalculate Body Surface Area (BSA) using Mosteller, Du Bois, Haycock, Gehan & George, or Boyd formulas.