Body fat percentage is the proportion of total body mass that is fat tissue. The ranges below are drawn from published literature — they describe how populations distribute, not prescriptions for any individual.
Body fat percentage ranges by sex
The categories below follow the framework used in ACSM's Guidelines for Exercise Testing and Prescription (11th ed., 2021). Essential fat is the minimum required for physiological function. All other categories are population-level descriptive ranges, not health targets.
| Category | Men | Women |
|---|---|---|
| Essential fat | 2–5% | 10–13% |
| Athletes | 6–13% | 14–20% |
| Fitness | 14–17% | 21–24% |
| Acceptable | 18–24% | 25–31% |
| Obese | ≥25% | ≥32% |
Women carry a higher essential fat percentage due to sex-specific fat depots (breast tissue, pelvis, and hormonal reserves). Ranges are for adults; thresholds differ for children and older adults.
Measurement method comparison
No field method matches the accuracy of the two laboratory reference methods (hydrostatic weighing and DEXA). The table below summarizes typical accuracy, common direction of error, and practical considerations for each approach. Error ranges assume correct technique; poor technique increases error in all methods.
| Method | Typical error vs. DEXA | Common error direction | Key variable | Practical notes |
|---|---|---|---|---|
| US Navy circumference | ±3–4% | Can overestimate in very lean individuals | Measurement site and technique | No cost, self-administered; useful for trend tracking |
| Skinfold (3–7 site) | ±3–4% | Underestimates in older adults (thinner skin) | Caliper quality and measurer training | Requires trained technician; inter-rater variability is high |
| Bioelectrical impedance (BIA) | ±3–5% | Underestimates when dehydrated; overestimates when overhydrated | Hydration status at time of measurement | Consumer scales and handheld devices; highly sensitive to protocol |
| DEXA (dual-energy X-ray) | ±1–2% (reference) | Slight overestimate in very obese individuals | Scanner calibration and software version | Clinical setting; provides regional breakdown (trunk, limbs) |
| Hydrostatic weighing | Reference method | Slight overestimate with high bone density | Residual lung volume measurement accuracy | Gold standard; requires specialized tank and trained staff |
The AHA 2023 Scientific Statement on body composition notes that DEXA has largely supplanted hydrostatic weighing as the clinical reference standard due to accessibility, though both remain valid reference methods (Prado et al., 2023).
US Navy formula reference
The circumference-based formula developed by Hodgdon and Beckett at the Naval Health Research Center (1984) estimates body fat from height and circumference measurements at specific sites.
Men (waist at navel, neck at larynx; all measurements in cm):
%BF = 495 / (1.0324 − 0.19077 × log₁₀(waist − neck) + 0.15456 × log₁₀(height)) − 450
Women (waist at narrowest point, hip at widest, neck at larynx; all measurements in cm):
%BF = 495 / (1.29579 − 0.35004 × log₁₀(waist + hip − neck) + 0.22100 × log₁₀(height)) − 450
The standard error of estimate for the men's equation is approximately 3.5% and for the women's equation approximately 3.7%, compared to hydrostatic weighing. The formula is most reliable in the 10–30% body fat range.
For the interactive body fat estimator using this formula, see the Body Fat Estimator →. For a BMI reference including WHO classification thresholds, see the BMI Calculator →.