Body Fat Percentage Calculator — Navy & Jackson–Pollock

The Body Fat Percentage Calculator — Navy & Jackson–Pollock offers two practical approaches that work at home or in a gym. The first is the US Navy circumference method, which uses height, neck, waist, and hip (for women) to estimate the proportion of fat. The second option uses skinfold calipers with Jackson–Pollock three-site or seven-site formulas, plus a Durnin–Womersley four-site choice many coaches like. Both paths end in the same place: a percentage that, paired with age and sex, helps you get a sense of where you are now and how progress looks over time.

The circumference approach is the quickest because it relies on a flexible tape measure you can keep in a drawer. Measure the neck at the narrowest point, the waist at the navel, and (for women) the hips at the widest buttock point. Height can be entered in centimeters or as feet and inches. Because the math depends on the log of the measurements, it is important to measure snugly but without compressing the skin. Take two readings and use the average if you have time.

Caliper-based methods sample pinchable subcutaneous fat in specific locations. Jackson–Pollock three-site uses chest, abdomen, and thigh for men, and triceps, suprailiac, and thigh for women. The seven-site version includes chest, midaxillary, triceps, subscapular, abdomen, suprailiac, and thigh. Durnin–Womersley uses four sites (biceps, triceps, subscapular, and suprailiac) and applies an age-specific equation. If you are new to calipers, ask a trainer to demonstrate how to grasp a vertical or diagonal fold and wait a second before reading the millimeters. Consistency matters more than perfection, so try to use the same side of the body and the same order each time.

What do the percentages mean? For men, rough categories often used in fitness include essential fat around two to five percent, athletes around six to thirteen percent, fitness fourteen to seventeen, average eighteen to twenty-four, and obesity at twenty-five and above. For women, essential tends to be ten to thirteen, athletes fourteen to twenty, fitness twenty-one to twenty-four, average twenty-five to thirty-one, and obesity at thirty-two and up. These bands are descriptive, not prescriptive. The healthiest number for you depends on history, sport, medications, and goals. Use the calculator to track trends alongside strength, stamina, sleep, and how your clothes fit.

• Take measurements at a consistent time of day, ideally before training and meals.
• Re-measure every two to four weeks; daily changes mostly reflect fluids.
• For calipers, take two or three readings per site and use the average.

Lean mass can be motivating to follow. If you enter your body weight, the page calculates fat mass and lean mass by simple subtraction. When recomposition is the goal—losing fat while maintaining or gaining muscle—lean mass stability week to week is a good sign your protein, training, and recovery are aligned. Pair the percentage here with sensible nutrition, progressive resistance training two to three days per week, and enough sleep to support recovery and appetite control.

Limits and cautions: tape and caliper estimates are just that—estimates. Hydration, recent workouts, menstrual cycle, and operator technique all influence readings. People with very high or very low body fat, elite bodybuilders, and those with certain medical conditions may see larger errors. Dexa, air displacement plethysmography, and multi-compartment models are more precise but are not always practical for regular use. Treat changes over months as the signal; ignore day-to-day noise.

Finally, remember that numbers are tools, not judgments. Many athletes perform best inside wide body-fat ranges, and health behaviors matter more than a single percentage. If you have a history of disordered eating or if the measurements bring stress, share that with a clinician or coach and opt for gentler tracking like strength landmarks, step counts, or minutes of activity. Used well, the Body Fat Percentage Calculator — Navy & Jackson–Pollock turns raw measurements into clear information you can act on without overthinking.

US Navy uses base-10 logarithms of circumference differences. Men: 86.010 × log10(waist − neck) − 70.041 × log10(height) + 36.76. Women: 163.205 × log10(waist + hip − neck) − 97.684 × log10(height) − 78.387. Jackson–Pollock skinfolds compute body density from the sum of sites and age, then apply the Siri equation: percent fat = 495 ÷ density − 450. Three-site (men: chest, abdomen, thigh; women: triceps, suprailiac, thigh) and seven-site use well-known coefficients; Durnin–Womersley uses log10 of the four-site sum with age- and sex-specific constants. All calculations run locally in your browser.