How to use the Body Fat Calculator
- Choose your sex and enter height and weight.
- Measure your neck below the larynx, your waist at the navel and (for women) your hips at the widest point.
- Read your body fat percentage, fat mass and lean mass.
How the Navy method works
The U.S. Navy formula estimates body fat from height and circumferences, because fat stored around the waist and hips changes those measurements more than muscle does. It is usually within 3–4 percentage points of a DEXA scan — good enough to track a trend, using the same tape and the same spot each time.
Typical ranges
| Category | Men | Women |
|---|---|---|
| Essential fat | 2–5% | 10–13% |
| Athletes | 6–13% | 14–20% |
| Fitness | 14–17% | 21–24% |
| Average | 18–24% | 25–31% |
| Above average | 25%+ | 32%+ |
Pair it with the BMI Calculator and the Calorie Calculator.
Also searched as: body fat percentage calculator, navy body fat calculator, body fat percentage, lean body mass calculator, fat mass calculator.
Tools that pair well with the Body Fat Calculator
- Ideal Weight Calculator — See your ideal weight by four well-known formulas and the healthy weight range (BMI 18.5–24.9) for your height.
- Macro Calculator — Turn your daily calories into grams of protein, carbs and fat for your goal.
- Water Intake Calculator — Estimate how much water to drink each day from your weight, how active you are and how hot it is — shown in liters, ounces and glasses.
- Roman Numeral Converter — Convert any number from 1 to 3,999,999 into Roman numerals — or read Roman numerals back as numbers — with a breakdown of every symbol.
Frequently asked questions
How accurate is the Navy body fat formula?
For most people it lands within a few percentage points of lab methods. Measure the same way each time and watch the trend rather than a single reading.
Why do women need a hip measurement?
Women store more fat around the hips, so the formula for women adds the hip circumference to improve accuracy.
Is anything I enter saved or sent?
No. The calculation runs in your browser. Your last inputs are remembered on this device only, so the page opens where you left off.
Can I install Body Fat Calculator as a web app and use it offline?
Yes. Body Fat Calculator is an installable web app (PWA) — installed from your browser, not downloaded from an app store. Click Install app at the top of this page in Chrome or Edge (Windows, macOS, Linux, ChromeOS) or on Android, use Share → Add to Home Screen on iPhone and iPad, or File → Add to Dock in Safari 17+ on a Mac. It then opens in its own window with its own icon, and because it runs entirely in your browser it keeps working offline. Firefox on desktop can’t install web apps. How installing works.