📊 Body Fat Calculator
Enter a few tape-measure readings to estimate your body fat percentage with the US Navy method, and see where it lands against standard fitness categories.
📏 Estimate Your Body Fat
What is the Body Fat Calculator?
It uses the US Navy tape-measure method to estimate body fat percentage from height and a few circumference readings — neck and waist for men, plus hip for women — instead of calipers, scales, or a lab scan.
Use it to get a quick baseline before starting a training programme, or to track changes over time alongside your onboard workouts. It's a fitness estimate, not a medical diagnosis, so treat the result as a trend indicator rather than a precise reading.
❓ Frequently Asked Questions
How does the Navy body fat method work?
It estimates body fat percentage from circumference measurements rather than skinfold calipers or scales. Men need height, neck, and waist; women need height, neck, waist, and hip. The formula plugs these into a log-based equation developed for the US Navy to keep fitness assessments consistent and low-cost.
How accurate is a tape-measure body fat estimate?
It's a solid estimate for tracking trends, typically within a few percentage points of more precise methods like DEXA scans or hydrostatic weighing. It won't be lab-accurate, but measuring the same way at the same time of day lets you track real progress over weeks and months.
Where exactly should I measure neck, waist, and hip?
Measure the neck just below the larynx, the waist at its narrowest point (roughly at the navel for most people), and — for women — the hip at its widest point around the buttocks. Keep the tape snug but not compressing the skin, and measure at the same time of day for consistency.
What do the fitness categories mean?
Essential fat is the minimum needed for basic health; athletic and fitness ranges reflect visibly lean, trained bodies; average covers typical healthy adults; and obese flags a level associated with higher health risk. Categories differ between men and women because women naturally carry more essential fat.