Estimate your body fat percentage using the U.S. Navy circumference method — accurate, simple, and requires only a tape measure.
Use a soft tape measure. Measure in the morning, relaxed, standing straight. Keep the tape snug but not tight.
Enter your measurements and click calculate to see your results.
Proper measurement technique is essential for accurate results.
Measure around the neck just below the larynx (Adam's apple), with the tape sloping slightly downward at the front.
Measure at the narrowest point of your torso, typically at the navel level or slightly above.
Measure at the widest point of your hips/buttocks, keeping the tape parallel to the floor.
Follow these tips to get the most accurate measurement possible.
The U.S. Navy body fat formula was developed by Hodgdon and Beckett at the Naval Health Research Center. It has been validated against hydrostatic weighing and typically has an accuracy of ±3-4% compared to laboratory methods.
Limitations: This method may be less accurate for very lean individuals (<10% body fat) or those with unusual body proportions. For the most accurate results, consider DEXA scanning or hydrostatic weighing.
Formula (Men): %BF = 86.010 × log₁₀(waist - neck) - 70.041 × log₁₀(height) + 36.76
Formula (Women): %BF = 163.205 × log₁₀(waist + hip - neck) - 97.684 × log₁₀(height) - 78.387