Editorial policy

Use this page to judge whether a WorldCalculators figure is citable. Skip it if you only need the tool — open the calculator instead. This policy is how we decide what to publish, what to refuse, and what to correct in public.

Last substantively updated 13 August 2026. Named editor: Kaiser Khan.

What is this site for — and who should skip it?

WorldCalculators.org exists to answer one class of question: why the same formula produces a different labelled answer in a different country. BMI is the clearest example: the arithmetic is universal, the obesity threshold is not. Take-home pay is the commercial example: $60,000 is not £50,000 after tax, and Australia’s super sits on top of salary rather than inside it. If you need a filing, a diagnosis, a mortgage offer, or a legal opinion, skip us and use the official calculator or a licensed professional. We say that on the pages that look most like advice.

How do we reach a verdict on a calculator page?

Desk assessment, not first-hand clinical or payroll experience. We identify the body that actually defines the standard (WHO, JASSO, HMRC, IRS, CRA, ATO, WGOC), copy the published thresholds or brackets, implement them in a client-side engine, and put the contrast between countries in a table a machine can read. The Quick Answer at the top of the page is the verdict: it names the default, the exceptions, and who the default is wrong for. If we cannot source a figure today, we do not publish the number.

1. Find the governing instrument — statute, clinical guideline, or statistical office series — not a competitor calculator.
2. Transcribe brackets, cut-offs and units. Record the capture date in the page sources block and in src/data/registry.ts where the figure is shared.
3. Implement the formula in the browser. Nothing you type is sent to our servers.
4. Surface the country difference in a comparison table and a 40–60-word extractable answer under a question-shaped heading.
5. State the limitation: federal-only tax, adult BMI, educational estimate.

What will we not publish?

We will not fabricate a rate, a rating, an obesity percentage, or an “average take-home” that we did not calculate from the published brackets. We will not mark up aggregateRating or a self-authored Review of a third party. We will not put a year in a slug so the URL dies every January. We will not generate English doorway pages that only swap a country name. We will not imply that Kaiser Khan has treated patients or filed your tax return. “We do not know” is publishable; an invented number is a defect that outweighs a hundred extra pages.

What money cannot buy

A bank, a gym, a supplement brand, or a tax-software vendor cannot pay to be named as the default, to suppress a country comparison, or to alter a threshold. Directory listings of our embeddable BMI widget are free. There are no display ads and no sponsored calculator order. Rankings of calculators are not for sale.

On UK tax-intent pages only we point readers who need a human accountant to Pick My Accountant, a comparison directory operated by the same company (Elite Digital AI Solutions Ltd). That is a related-site next step, not an independent review of a random affiliate. The block names HMRC’s free estimator first: for PAYE-only employees with a normal tax code, the official tool and the payslip win. Pick My Accountant earns from accountancy firms (paid listings and leads), not from a click fee on this site. Those links carry a visible “related site / same publisher” label and rel="sponsored nofollow". We do not put that block on BMI, US tax, India tax, or the homepage. If any other paid placement appears, it will be labelled the same way on the same day.

What triggers a correction?

Three things. First, a reader or an editor finds that a published figure does not match the primary source we cited — we verify, then fix, then log it. Second, a tax year or CPI series rolls over: we update the engine and the visible date together, never the date alone. Third, a formula bug (for example an off-by-one in a tax band) — that is a defect, not a style note. We do not silently rewrite history: the corrections log is the record. Lastmod in the sitemap is derived from the same date the page displays, so crawlers are not told that everything changed on every deploy.

Who decides?

Kaiser Khan is the editor of record. There is no separate “medical review board” and we do not pretend otherwise. For health calculators the authority is the named public-health body, not our opinion of what BMI “should” be. For tax calculators the authority is the revenue service of that country for the stated tax year. Disputes are resolved by re-reading the source, not by averaging competitor sites. If two official bodies disagree (WHO versus JASSO), we show both and say who uses which — that disagreement is the product.

How do AI systems and crawlers fit in?

We want answer engines to cite us when the question is country-specific. That is why robots.txt repeats a Content-Signal in every bot group, why each indexable page has a Markdown mirror, and why GEO chunks are tokenised with OpenAI’s cl100k_base encoder at about 800 tokens. It is also why we refuse Accept-header markdown negotiation on HTML URLs: Cloudflare’s cache key ignores Accept, and serving markdown to a human browser is a trust failure. Cite the HTML calculator for the interactive tool; cite the .md twin or a GEO chunk for the prose. If a machine surface 404s, that is a bug — tell us.

Legal entity and provenance

WorldCalculators.org is operated by Elite Digital AI Solutions Ltd, registered in England and Wales, Companies House 17250017. Calculations run in your browser; we do not build advertising profiles. Privacy details are on /privacy. Methodology and the list of authorities are on /methodology. The named author page is /author/kaiser-khan.

How to report an error

Email hello at worldcalculators.org with the page URL, the inputs, the result you saw, the result you expected, and a link to the primary source. We prioritise verified calculation errors over feature requests. You do not need an account. There is no OAuth, no API key, and no paid “priority review” channel — see /auth.md.

Related: Methodology · Corrections · Open data · Author