Body Fat Calculator
Estimate your body fat percentage with the U.S. Navy method. Just a tape measure, no scale needed. Works in inches or centimeters, shows your category and what a given range looks like.
This is an estimate with a typical error of plus or minus 3 to 4 percent. The trend over weeks matters more than any single reading. Always measure first thing in the morning, fasted, the same way. General information, not medical advice.
What each body fat range roughly looks like
An approximation, fat distribution is individual. Calculate your value above and the matching range gets highlighted.
How to measure correctly
The whole accuracy of this method comes down to clean tape measurements. Take them in the morning, before eating or drinking, standing relaxed.
- Neck: just below the larynx (Adam's apple), tape sloping slightly downward to the front.
- Waist: men measure at the navel; women at the narrowest point. Snug, not compressing the skin. Breathe out normally, do not suck in.
- Hip (women): around the widest part of the buttocks.
- Keep the tape horizontal and take each measurement twice, then average.
Healthy body fat percentage by sex
Women naturally carry more essential fat than men, so the healthy ranges differ. These are general orientation ranges, not strict cut-offs.
| Category | Men | Women |
|---|---|---|
| Essential fat | 3 to 5% | 12 to 14% |
| Athletic | 6 to 13% | 15 to 20% |
| Fit | 14 to 17% | 21 to 25% |
| Average | 18 to 24% | 26 to 32% |
| Elevated | 25%+ | 33%+ |
Body fat measurement methods compared
Every at-home method is an estimate. The point is to pick one, use it consistently, and watch the trend.
| Method | Accuracy | Cost | Good for |
|---|---|---|---|
| Tape measure (Navy) | ± 3 to 4% | Free | Tracking at home, this calculator |
| Skinfold calipers | ± 3% | Low | Consistent self-tracking with practice |
| Smart scale (BIA) | ± 4 to 8% | Low | Convenience, daily trend only |
| DEXA scan | ± 1 to 2% | High | A precise one-off baseline |
How accurate is this calculator?
The U.S. Navy formula was validated against hydrostatic weighing and lands within roughly 3 to 4 percentage points for most people. It is least accurate at the extremes and for very muscular builds, because it infers fat from circumferences rather than measuring it directly. That is fine for the job most people actually have, which is seeing whether the number is moving in the right direction over weeks.
How to lower your body fat
Two levers do almost all the work, and neither is a crash diet.
- A moderate calorie deficit. Aim to lose about 0.5 to 1 percent of body weight per week. Faster usually costs you muscle.
- Strength training plus enough protein. This is what tells your body to keep muscle while it burns fat, so the weight you lose is fat, not tissue you want.
- Sleep and steps. Unglamorous, but poor sleep and a sedentary day quietly stall fat loss.
Frequently asked questions
How do I measure body fat at home?
Use a soft tape measure. Men measure neck and waist (at the navel); women add the hip at its widest point. Keep the tape snug but not tight, breathe normally, and measure in the morning before eating. Enter the numbers above and the calculator applies the U.S. Navy formula.
How accurate is the U.S. Navy body fat calculator?
For most people it lands within about 3 to 4 percentage points of a DEXA scan, which is good enough to track progress. It is less reliable at the extremes (very lean or very high body fat) and for very muscular builds. Use the trend over weeks, not a single reading.
What is a healthy body fat percentage?
For men, roughly 10 to 20 percent is healthy; for women, roughly 18 to 28 percent, partly because women carry more essential fat. Athletes sit lower. Going below the essential minimum (about 3 to 5 percent for men, 12 percent for women) is not sustainable or healthy.
Is body fat percentage better than BMI?
Usually yes. BMI cannot tell muscle from fat, so a lean, muscular person can read as "overweight". Body fat percentage measures what actually matters for health and appearance, which is how much fat you carry.
How fast can I lower my body fat?
A sustainable rate is about 0.5 to 1 percent of body weight lost per week through a moderate calorie deficit plus strength training to keep muscle. Faster usually means losing muscle and water, not just fat.