Body Fat Calculator

Estimate your total body fat percentage using the U.S. Navy Method or the BMI Method. For the most accurate results, measure to the nearest ¼ inch (0.5 cm). (both of which are outlined below).

US Units

Metric Units

Gender -- Select -- Male Female

Age

Weight

Height

Neck

Waist

Hip

Weight

Height

Neck

Waist

Hip

Body Fat: --

Body Fat (U.S. Navy Method)	--
Body Fat Category	--
Body Fat Mass	--
Lean Body Mass	--
Body Fat (BMI method)	--

How to Use

1. Select your gender and enter your age.
2. Input your weight (in pounds or kilograms) and height (in feet/inches or centimeters).

3. Measure and enter:

- Neck circumference (below the larynx, tape sloping downward).

- Waist circumference:
    Men: Measure horizontally at the navel.
    Women: Measure at the smallest width.
    Women only: Hip circumference (widest point).

4. Click Calculate to view your results.

---

Results Explained

- Body Fat Percentage (U.S. Navy Method): Estimates fat using neck, waist, and (for women) hip measurements.

- Body Fat Category: Compares your result to fitness standards (Essential, Athlete, Fitness, Average, Obese).
- Fat Mass & Lean Mass: Breaks down fat vs. muscle/other tissue.
- Ideal Body Fat (Jackson & Pollock): Shows the recommended fat percentage for your age.
- BMI Method Estimate: Alternative calculation using BMI, age, and gender.

---

Understanding Body Fat

- Essential Fat: Minimum required for health (2–5% men, 10–13% women).

- Storage Fat: Excess fat, which can increase health risks if too high.
- Health Risks: Obesity is linked to heart disease, diabetes, and other conditions.

---

Measurement Methods

1. U.S. Navy Method: Uses waist, neck, and hip (women) measurements.

- Men:

$$\text{BFP}=86.010\times {\log }_{10}(\text{waist}-\text{neck})-70.041\times {\log }_{10}(\text{height})+36.76$$

- Women:

$$\text{BFP}=163.205\times {\log }_{10}(\text{waist}+\text{hip}-\text{neck})-97.684\times {\log }_{10}(\text{height})-78.387$$

2. BMI Method: Estimates fat based on BMI, age, and gender. 

- Men:

$$\text{BFP}=1.20\times \text{BMI}+0.23\times \text{Age}-16.2$$

- Women:

$$\text{BFP}=1.20\times \text{BMI}+0.23\times \text{Age}-5.4$$

---

Accuracy Notes

These calculations are estimates. For precise measurements, consider professional methods like:

- Bioelectrical Impedance Analysis (BIA)

- Hydrostatic Weighing
- DEXA Scan

---

Body Fat Categories

Classification	Women	Men
Essential Fat	10–13%	2–5%
Athletes	14–20%	6–13%
Fitness	21–24%	14–17%
Average	25–31%	18–24%
Obese	32%+	25%+