Estimate your body fat percentage using 3 scientific methods — US Navy tape measure, BMI-based, and skinfold. Get your fat mass, lean mass, and fitness category.
Measurement Method
📏US Navy Method (Most accurate)
⚖️BMI-Based (Least accurate)
🤏3-Site Skinfold (Needs calipers)
years
kg
cm
📐Measure all circumferences at the widest point, keeping the tape horizontal. Take 2–3 readings and average them.
cm
cm
At navel for men, narrowest point for women
cm
At widest point
⚠️ BMI-based body fat estimation is the least accurate method — it cannot distinguish muscle from fat. Use Navy or skinfold for better results.
🤏Use skinfold calipers. Pinch the skin and fat away from muscle, apply calipers 1cm from fingers. Read after 2 seconds.
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Body fat categories differ between men and women due to hormonal differences and reproductive needs. For men: essential fat 2–5%, athletes 6–13%, fitness 14–17%, average 18–24%, obese 25%+. For women: essential fat 10–13%, athletes 14–20%, fitness 21–24%, average 25–31%, obese 32%+. A small amount of essential fat is necessary for normal physiological function.
Which Body Fat Method Is Most Accurate?
DEXA scan is the gold standard (±1–2% error) but requires clinical equipment. Underwater weighing is highly accurate but impractical. Skinfold calipers with proper technique are accurate to ±3–4%. The US Navy tape measure method is about ±3–4% and requires only a tape measure. BMI-based formulas are the least accurate (±5–8%) and cannot distinguish muscle from fat.
Use the Body Fat Calculator above — enter your values and get instant results. This free online tool calculates how to calculate body fat percentage without any download or signup required. Results update in real time as you type.
Use the Body Fat Calculator above — enter your values and get instant results. This free online tool calculates body fat calculator no equipment without any download or signup required. Results update in real time as you type.
The US Navy circumference method has an error range of approximately ±3–4% when measurements are taken correctly. It's the best option for home measurement without equipment. Take 3 measurements at each site and average them, keeping the tape level and snug but not compressing skin.
For men, 14–24% is the healthy range. For women, 21–31%. Below essential fat levels (under 5% for men, under 13% for women) can impair hormonal function, immune response, and organ protection. Athletic levels (6–13% men, 14–20% women) are healthy if maintained without extreme restriction.