Body Fat Calculator

Body Fat Percentage

Understanding your body fat percentage and BMI (Body Mass Index) is essential for tracking your health, fitness, and overall wellness. Both metrics provide insight into whether your weight and body composition are within a healthy range, helping you make informed decisions about diet, exercise, and lifestyle.

Body Fat Categories

Body fat serves important functions in the body. It stores energy, cushions organs, provides insulation, and produces essential hormones. Body fat is generally divided into two types:

1. Essential Fat: Necessary for life and reproductive function.

   • Women: 10–13%

   • Men: 2–5%

2. Storage Fat: Fat stored beneath the skin (subcutaneous) or around organs (visceral). While some storage fat is healthy, excess fat increases health risks.

American Council on Exercise Body Fat Classification

Jackson & Pollock Ideal Body Fat by Age

Health Risks of Excess Body Fat

Excess body fat can lead to overweight and obesity, which significantly increase the risk of:

• Heart disease and stroke

• Type 2 diabetes and insulin resistance

• High LDL (“bad”) cholesterol and low HDL (“good”) cholesterol

• Certain cancers (breast, colon, kidney)

• Obstructive sleep apnea

• Reduced quality of life and mental health challenges

Visceral fat, located around organs, is particularly dangerous as it disrupts hormone balance and increases inflammatory markers.

Measuring Body Fat Percentage

Several methods exist to estimate body fat percentage. Here are the most commonly used approaches:

1. U.S. Navy Method

The U.S. Navy method estimates body fat using circumference measurements.

For Men:

• Measure waist at navel level

• Measure neck circumference

• Use the formula:

USC Units:
BFP = 86.010 × log10(waist − neck) − 70.041 × log10(height) + 36.76

Metric Units:
BFP = 495 / (1.0324 − 0.19077 × log10(waist − neck) + 0.15456 × log10(height)) − 450

For Women:

• Measure waist, neck, and hip (widest point)

• Use the formula:

USC Units:
BFP = 163.205 × log10(waist + hip − neck) − 97.684 × log10(height) − 78.387

Metric Units:
BFP = 495 / (1.29579 − 0.35004 × log10(waist + hip − neck) + 0.22100 × log10(height)) − 450

Fat Mass (FM) & Lean Mass (LM) Calculations:

• FM = BFP × Weight

• LM = Weight − FM

2. BMI Method to Estimate Body Fat

Your BMI can also provide a reliable estimate of body fat percentage. Use a BMI calculate tool to find your BMI first, then apply the formulas:

Adult Males:
BFP = 1.20 × BMI + 0.23 × Age − 16.2

Adult Females:
BFP = 1.20 × BMI + 0.23 × Age − 5.4

Boys:
BFP = 1.51 × BMI − 0.70 × Age − 2.2

Girls:
BFP = 1.51 × BMI − 0.70 × Age + 1.4

This method is especially useful for quick estimates and when advanced measurement tools are unavailable.

Body Fat, BMI, and Healthy Ranges

• Men: Healthy BFP: 8–19%

• Women: Healthy BFP: 21–33%

• Obese: Men > 25%, Women > 32%

• Athletes: Men 6–13%, Women 14–20%

Note: Being overweight based on BMI does not always indicate excess body fat. Highly muscular individuals may have high BMI but low body fat.

Key Takeaways

• Body fat is essential for hormone function, insulation, and energy storage.

• Excess body fat, especially visceral fat, increases health risks.

• Use BMI calculate tools or the U.S. Navy method to estimate body fat percentage.

• Maintain a healthy range of body fat for overall wellness, longevity, and fitness.

• Lifestyle factors such as diet, exercise, and hormone balance affect body fat distribution and levels.