justyourcalculatorBody Fat Calculator
Estimate body fat from a few tape measurements.
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Body Fat Calculator
Body fat % by the US Navy tape and BMI methods
Just below the larynx, tape sloping slightly down to the front.
Men: at the navel. Women: at the narrowest point.
Body fat (US Navy method)
17.4%
Fitness
- Body fat category (ACE)
- Fitness
- Body fat mass
- 27.9 lb
- Lean body mass
- 132.1 lb
- Ideal body fat for your ageJackson & Pollock
- 12.7%
- Fat to lose to reach ideal
- 8.7 lb
- Body fat (BMI method)Deurenberg formula, a rougher estimate
- 18.2%
Measurements in cm. Tape methods are usually within 3 to 4 percentage points of lab tests (DEXA, hydrostatic weighing). Measure on bare skin, relaxed, and average two or three readings.
- Fat (lb)27.9
- Lean (lb)132.1
How it was calculated
- Navy (men): 495 / (1.0324 - 0.19077 × log10(waist - neck) + 0.15456 × log10(height)) - 450
- = 495 / (1.0324 - 0.19077 × log10(48.3) + 0.15456 × log10(177.8)) - 450 = 17.4%
| Category | Body fat |
|---|---|
| Essential fat | 2 - 5% |
| Athletes | 6 - 13% |
| Fitness | 14 - 17% |
| Average | 18 - 24% |
| Obese | 25%+ |
More Fitness & Health Calculators
View all calculators- Army Body Fat CalculatorThe Army's one-site tape test and standards
- Lean Body Mass CalculatorLean body mass by Boer, James and Hume
- BMI CalculatorBody mass index and healthy weight range
- Ideal Weight CalculatorIdeal weight by four formulas plus healthy BMI range
- Body Type CalculatorYour body shape from bust, waist and hips
- Calorie CalculatorDaily calories to maintain, lose or gain weight
- BMR CalculatorBasal metabolic rate by three formulas
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How the body fat calculator works
The US Navy method (Hodgdon and Beckett, 1984) predicts body fat from height and neck and waist circumference, plus hip circumference for women. It uses base-10 logarithms of the measurements in centimeters.
The BMI method (Deurenberg, 1991) estimates body fat from BMI, age and sex: 1.20 × BMI + 0.23 × age - 10.8 × sex - 5.4 for adults (sex = 1 for men, 0 for women). It's rougher because BMI can't see muscle.
Categories follow the American Council on Exercise. The ideal for your age comes from Jackson and Pollock's research, which found healthy body fat rises slowly with age.
Using and checking your result
Published by JustYourCalculator. Check the units and assumptions above, and compare a known example before relying on the output. Calculations use browser arithmetic and may round displayed values.
This tool provides an estimate, not a diagnosis, treatment plan or individualized medical advice. Population formulas may not fit children, pregnancy, athletes or people with health conditions. Discuss health decisions with a qualified clinician.
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