Every FitTop calculator uses a public formula with a fixed version, a verifiable example and clearly stated limits of applicability. Every article relies on sources and carries a last-reviewed date.
How formulas are chosen
A formula makes it onto the site only if it is:
- public and recognised. The source is an official guideline, a peer-reviewed study or a textbook; the formula can be checked against the original;
- reproducible. Every calculator has a verifiable example with concrete inputs and an expected result — it matches what the code does and is pinned by a unit test;
- bounded. Accepted input values, formula limitations and the situation "the tool does not fit here" are stated on the calculator page.
Calculations are implemented as pure functions isolated from the interface and covered by tests: formulas, boundaries, invalid input and rounding.
The formula version changes with any change to the algorithm, boundaries or rounding. The current version of each formula is listed in the table below; the same version appears on the calculator page.
How programs are checked
Training programs are general starting plans for healthy adults. Every program must have: sources, contraindications, a progression rule and exercise substitutions. A program goes through editorial review and does not promise results that cannot be substantiated.
How material is updated
Material follows the process: outline → source collection → draft → fact check → editorial review → publication. The last-reviewed date is shown on every page. A substantive update changes the update date; a change to a calculator formula changes the formula version and the verifiable example.
How to report an error
If there is a mistake in material or in a calculation, write to us through the Contact page: give the page address, what it says, what you expected instead and the source if you know it. Substantive corrections are reflected in the page update date.
Formula versions for every published calculator are listed in the table below; the same version appears on each calculator page.