People first
Content is written to help a visitor complete a calculation or understand a practical question. We avoid adding paragraphs merely to reach a word count. A useful page should explain what the tool does, what information it needs, how to interpret the answer and where its limits matter.
Accuracy and sources
Standard mathematical relationships are checked against their definitions. Time-sensitive claims—such as tax years, government thresholds or provider rules—should name the relevant period and be checked against an authoritative source. Articles distinguish a mathematical example from advice about what a particular person should do.
Originality and automation
Software helps us build and test a consistent calculator interface, but publishing many pages is not a substitute for usefulness. Pages selected for search indexing are reviewed for a clear purpose, working calculator, meaningful explanation and appropriate limitations. Thin utility and duplicate archive pages are intentionally excluded from search results.
Commercial independence
Advertising may fund the site, but advertisers do not choose calculator formulas or alter results. A paid relationship or affiliate link will be disclosed where it applies. We do not present advertisements as navigation, calculator controls or editorial recommendations.
Corrections
Clear factual or calculation errors are corrected in the maintained source and then republished. Wording may also be revised when it could cause a reasonable visitor to misunderstand a result. To report a concern, follow the guidance on our contact page.
Last reviewed: 19 July 2026