Body Fat Calculator
Estimate your body fat percentage using the U.S. Navy tape method. Enter a few measurements in inches to get your body fat and fitness category.
Measure at the widest point for waist/hip and just below the larynx for neck, in inches. The U.S. Navy tape method is an estimate (±3–4%); calipers or a DEXA scan are more precise. Not medical advice.
How to use this calculator
Choose your sex, then enter your height, neck, and waist measurements (women also add hip), all in inches. The calculator returns your estimated body fat percentage and which fitness category it falls into.
How it works
The U.S. Navy method correlates body fat with body circumferences. Because fat distributes around the waist and hips, measuring those against neck and height gives a surprisingly good estimate without calipers or lab equipment — ideal for tracking changes over time.
Measuring tips
Use a flexible tape, keep it level and snug (not tight), measure on bare skin, and take each measurement twice and average it. Measure at the same time of day for consistent tracking.
Body fat percentage is an estimate, not a diagnosis. For medical decisions, consult a healthcare professional.
Frequently asked questions
How does the U.S. Navy body fat method work?
It estimates body fat from tape measurements. For men it uses height, neck, and waist; for women it adds the hip measurement. The circumferences are plugged into a logarithmic formula to estimate body fat percentage.
How accurate is it?
The Navy method is typically within 3–4% of more precise methods like DEXA scans for most people. It's far more convenient, but accuracy depends on consistent, correct measurements.
Where do I measure?
Measure your neck just below the larynx, your waist at the navel (men) or the narrowest point (women), and hips at the widest point (women). Keep the tape snug and level, and measure in inches.
What is a healthy body fat percentage?
General ranges: for men, ~6–17% is athletic to fit and ~18–24% average; for women, ~14–24% is athletic to fit and ~25–31% average. Essential fat is around 2–5% (men) and 10–13% (women).