Body Fat Calculator
Calculate your body fat percentage using the US Navy method. This formula uses your height and body circumference measurements.
Body fat classification adjusts based on your age group
Used to calculate fat mass and lean mass breakdown
Measure just below the larynx (Adam's apple), tape level and snug
Measure horizontally at the navel. Do not suck in your stomach.
Age-Adjusted Body Fat Categories
Healthy body fat ranges shift with age as metabolism and fat distribution change. Categories below reflect age-adjusted standards.
Men
| Category | 18-29 | 30-39 | 40-49 | 50-59 | 60+ |
|---|---|---|---|---|---|
| Essential Fat | 2-5% | 2-5% | 2-5% | 2-5% | 2-5% |
| Excellent | 6-13% | 6-14% | 6-16% | 6-17% | 6-18% |
| Good | 14-17% | 15-18% | 17-20% | 18-21% | 19-22% |
| Average | 18-22% | 19-23% | 21-25% | 22-27% | 23-28% |
| Above Average | 23%+ | 24%+ | 26%+ | 28%+ | 29%+ |
Women
| Category | 18-29 | 30-39 | 40-49 | 50-59 | 60+ |
|---|---|---|---|---|---|
| Essential Fat | 10-13% | 10-13% | 10-13% | 10-13% | 10-13% |
| Excellent | 14-20% | 14-21% | 14-23% | 14-24% | 14-25% |
| Good | 21-24% | 22-25% | 24-27% | 25-28% | 26-29% |
| Average | 25-31% | 26-32% | 28-34% | 29-35% | 30-36% |
| Above Average | 32%+ | 33%+ | 35%+ | 36%+ | 37%+ |
How Age Affects Body Fat
As you age, your body naturally redistributes and stores fat differently. Metabolic rate decreases, lean muscle mass declines, and hormonal shifts (particularly testosterone in men and oestrogen in women) affect where and how much fat your body retains.
This is why the same body fat percentage can be classified differently for a 25-year-old versus a 50-year-old. The categories above reflect age-adjusted standards used by fitness professionals worldwide.
How to Measure
Take each measurement 3 times and use the average. Use a flexible tape measure, held snug but not compressing the skin.
Measure the circumference just below the larynx (Adam's apple). Keep the tape level, head straight, shoulders relaxed. Do not flex your neck.
Measure horizontally at the navel (belly button). Exhale normally — do not suck in your stomach. This is NOT the narrowest part of your waist.
Measure at the narrowest point of the natural waist, typically above the hip bone and below the rib cage.
Measure at the widest point of your hips/buttocks while standing with feet together.