Body Fat Calculator

The Body Fat Calculator estimates your body fat percentage based on measurements like your waist, neck, and height. This tool helps fitness enthusiasts and athletes track body composition health more accurately than weight alone. Whether you are planning to lose weight, gain muscle, or monitor fitness progress, this calculator provides the data you need to succeed. It uses proven methods like the U.S. Navy Method for reliable results.

Enter your body weight (in pounds)
Enter your height (in inches)
Enter your age (in years)
Enter your waist measurement (in inches)
Enter your neck measurement (in inches)

How Body Fat Percentage Is Calculated

Body fat percentage is the proportion of your total weight that consists of adipose tissue compared to lean mass. This tool primarily employs the U.S. Navy Method, a trusted formula that estimates body density using simple tape measurements. First, we measure the difference between your waist and neck circumferences to determine your body's core density. Then, we apply a logarithmic calculation factoring in your height to convert this density into a fat percentage. This step-by-step approach ensures you get a reliable estimate without needing expensive equipment, making it ideal for regular fitness tracking.

BF% = 495 / (1.0324 - 0.19077(log(waist - neck)) + 0.15456(log(height))) - 450

Where:

  • Measurements are in inches
  • Height is rounded to the nearest inch

What Your Body Fat Percentage Means

Your result indicates the specific amount of fat weight you carry, which is a better health indicator than BMI alone. This metric helps you understand if you are in a healthy range for your age and gender.

  • Losing Weight: If your result is over 25% (men) or 32% (women), aim for a caloric deficit to lower your body fat into the "Fitness" category safely.
  • Building Muscle: Athletes typically aim for 6-13% (men) or 14-20% (women) to maximize performance while maintaining essential fat stores.
  • General Health: Staying within the "Average" or "Fitness" ranges indicates a lower risk of obesity-related health issues.

Important Note

Hydration levels can affect tape measurements. For consistent tracking, measure yourself at the same time of day, ideally in the morning.

This calculator is for informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition.

To see changes in your body composition, retake your measurements every 4 weeks and adjust your diet or exercise plan as needed.

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