The Useful Site publishes calculators and explanations to help people reach sensible answers. This policy describes how pages are chosen, written, checked and corrected.
What I publish
A page must solve a recognisable problem. It may answer a common question, support a practical project or provide a specialist educational calculation. A tool does not have to appeal to everybody, but it must have a clear purpose for the person who needs it.
I do not publish a page simply to make the site look larger. New ideas are judged by whether the inputs can be explained, the result can be interpreted honestly and the method can be tested.
How pages are written
Pages are written in British English for readers who may be unfamiliar with the subject. Necessary technical terms are explained rather than left as unexplained jargon.
I avoid padded introductions, exaggerated claims and paragraphs added only to increase word count. A page should get to the point, then provide enough explanation for the reader to understand what the result means.
Exact calculations and estimates
Not every calculator produces the same kind of answer. Arithmetic such as area, volume or unit conversion may be exact once the measurements are known. Other tools depend on typical rates, user-supplied assumptions, published models or incomplete information.
Where a result is an estimate, I identify the main assumptions and limitations on the page itself. I do not present a broad guide as a professional diagnosis, valuation, legal conclusion or guaranteed outcome.
Sources and references
When a calculation depends on external guidance, I prefer primary or recognised sources: government departments, regulators, standards organisations, official product documentation and peer-reviewed research.
A reference is included because it supports the method or explanation—not because a long list of links makes a page look authoritative.
Health, finance and forensic science
These subjects can affect important decisions, so they receive additional caution. The tools are educational aids. They are not substitutes for a clinician, regulated financial adviser, solicitor, forensic practitioner or other suitably qualified professional.
Pages in these areas separate calculation from interpretation, and claim no more certainty than the method supports.
Advertising and editorial independence
Advertising helps pay for hosting and maintenance. It does not determine a calculator's formula, alter a result or buy a favourable conclusion.
The site does not accept payment to disguise promotional material as an independent calculation or editorial recommendation.
Corrections
Mistakes can happen in code, wording or source interpretation. When a credible problem is reported, the aim is to reproduce it, check the method and correct the page where necessary.
A report is most useful when it includes the page name, the figures entered, the result received and the expected result. Corrections can be reported through the Contact page.
Reviewing older pages
The site grew quickly, and some early pages are shorter than the standard now being introduced. Those pages are being reviewed subject by subject. A review may improve the explanation, testing, metadata, accessibility, references or the calculator itself.
Use of automated tools
Software may assist with coding, checking repetitive site elements or identifying inconsistencies. It does not remove the need to review the purpose, wording, formula, limits and behaviour of a page before publication.