How to Calculate Body Fat Percentage

The U.S. Navy circumference method estimates body fat from neck, waist, and (for women) hip measurements. It requires only a flexible tape measure.

Step-by-step

1. Measure neck below the larynx (Adam's apple), keeping tape horizontal.
2. Measure waist at the navel level after a normal exhale — do not suck in.
3. Women: measure hips at the widest point of the buttocks.
4. Record height accurately — it enters the formula.
5. Enter measurements into our Body Fat Calculator for the Navy formula result.
6. Compare to ACE categories: men 6–24% essential/athletic/fitness/acceptable; women 14–31%.

Tips and common mistakes

• Take measurements in the morning before eating
• Use the same tape position each time for trend tracking
• Accuracy is ±3–4% — use for trends, not absolute precision

Open the Body Fat Calculator to apply these steps with your own numbers instantly.

Frequently asked questions