Formula and page model
A calculator is treated as a product feature, not a one-off page. The expected inputs, units, output labels, rounding behavior, assumptions, fixtures, and sources belong to the calculator packet before the page is promoted.
The public page then renders meaningful HTML for the calculator, formula explanation, example, FAQ, related links, and source notes.
Risk levels
Calculators are classified by topic risk. Stable arithmetic and conversion tools are lower risk. Finance, health, tax, insurance, legal, and investment topics require stronger source notes and visible disclaimers.
- A: low-risk tools such as percentages, dates, and simple conversions.
- B: medium-risk tools such as loans, BMI, calories, GPA, and compound interest.
- C: higher-risk topics that can affect money, health, legal, tax, insurance, or investment decisions.
Search and indexability
Indexable pages need a stable canonical URL, title, H1, meta description, useful first HTML response, related links, FAQ when appropriate, and sitemap inclusion. Finance and health C-risk pages may be indexed only after their source, disclaimer, fixture, and independent-verification gates pass; other C-risk pages can remain available for review while staying noindex.