How This Calculator Works

This calculator uses the U.S. Navy body fat formula, which estimates body fat percentage based on circumference measurements. The formulas are:

For Men:
Body Fat % = 495 / (1.0324 - 0.19077 × log10(waist - neck) + 0.15456 × log10(height)) - 450

For Women:
Body Fat % = 495 / (1.29579 - 0.35004 × log10(waist + hip - neck) + 0.22100 × log10(height)) - 450

While not as accurate as methods like DEXA scans or hydrostatic weighing, the Navy method provides a reasonable estimate using simple measurements.

Understanding Body Fat Categories

Men:

Essential Fat (2-5%): Minimum needed for basic physical and physiological health
Athletes (6-13%): Typical for athletes, very lean
Fitness (14-17%): Fit appearance with visible muscle definition
Average (18-24%): Acceptable body fat for general health
Obese (25%+): Increased health risks

Women:

Essential Fat (10-13%): Minimum needed for basic health
Athletes (14-20%): Typical for female athletes
Fitness (21-24%): Fit appearance with muscle tone
Average (25-31%): Acceptable for general health
Obese (32%+): Increased health risks

Tips for Accurate Measurements

Take measurements in the morning before eating or exercising
Use a flexible measuring tape (cloth or plastic, not metal)
Keep the tape snug but don't compress the skin
Take measurements 2-3 times and use the average
Stand naturally - don't flex or suck in your stomach
Measure on bare skin for most accurate results
Track measurements weekly to monitor changes over time

Limitations & Considerations

The Navy method is an estimate - accuracy varies by individual
More accurate for people with average body types
May be less accurate for very lean or obese individuals
Muscle distribution can affect accuracy
Consider using multiple methods for best assessment
Focus on trends over time rather than single measurements
Body fat percentage is just one measure of health

Frequently Asked Questions

What is a healthy body fat percentage?

For men, 10-20% is considered healthy and fit, while 21-25% is acceptable. For women, 18-28% is healthy and fit, while 29-32% is acceptable. Essential fat minimums are about 2-5% for men and 10-13% for women.

How accurate is the body fat calculator?

This calculator uses the U.S. Navy method based on body measurements, which provides a reasonable estimate (within 3-4% of actual). For more precise readings, consider DEXA scans or hydrostatic weighing.

Why is body fat percentage better than BMI?

Body fat percentage directly measures how much of your weight is fat versus lean mass. BMI only considers height and weight, so a muscular person could have a high BMI but low body fat. Body fat gives a more accurate picture of health.

Body Fat Percentage Calculator

📏 Measurement Tips

Basic Information

Body Measurements

Circumference Measurements

Your Body Composition Results

Body Fat Percentage Ranges