Formula Governance
Body Fat Calculator — Change Log
Every formula on HealthCalcNow is version-controlled. This page records the formula behind the Body Fat Calculator — its current version, the source it comes from, and any revision made since publication.
Current version
Reference. 'Prediction of Percent Body Fat for U.S. Navy Men and Women from Body Circumferences and Height', Naval Health Research Center, 1984
Why this confidence level. Circumference-based method; roughly ±3–4% versus DEXA-scan ground truth.
Revision history
How we version formulas
A calculator's math lives in an isolated module with its own version number. Changing anything that affects a result — a coefficient, a category cutoff, a rounding rule, or the cited source — requires a version bump and an entry on this page. We don't silently edit formulas.
A last-reviewed date is different from a revision: it records when we last checked the formula against its published source and confirmed it still matches. A formula can be reviewed many times without changing.
We take our values from published public-health and scientific sources rather than deriving them ourselves, and we don't claim clinician review that hasn't happened. Read more in our methodology.