Trust

Editorial Policy

Last updated: July 29, 2026

Everything published on xyz calculatorz — calculators, explanations, examples and FAQs — is held to the standards below. This page is maintained by the site owner and describes our own practices; it is not an independent certification.

Content standards

Accuracy

A calculator ships only when its implementation reproduces the reference values of its source formula. Explanations must describe what the code actually does — if the tool excludes taxes, the copy says so.

Clarity

We write for a reader who is competent but not specialist: plain language first, notation second, and a worked example wherever a formula appears. Jargon is defined at first use.

Transparency

Formulas, variables, assumptions and exclusions are printed on the page. We do not present estimates as guarantees, and we label content that is educational rather than advisory.

Review process

Formula verification. Each formula is traced to a primary source and tested against known values before publication.
Paired review. Maths and prose are reviewed together so the explanation can never drift from the implementation.
Content updates. Pages are revisited when their underlying source changes — new rates, revised standards, updated clinical guidance.
Continuous improvement. Reader questions that recur become new FAQ entries, new examples, or new inputs on the tool itself.

Sources and references

Government sources — tax authorities, statistical agencies, health departments and regulators for rules, thresholds and official definitions.
Industry standards — recognised conventions for finance (day-count, compounding), construction (coverage rates, waste allowances) and measurement (SI unit definitions).
Academic references — peer-reviewed literature and established textbooks for clinical and mathematical formulas.

Where reputable sources conflict, we adopt the most widely used convention and disclose the alternative. Full detail on sourcing is in our calculation methodology.

Corrections policy

Report an issue through the contact page with the calculator URL and the inputs you used.
We reproduce the result and compare it against the source formula, usually within two business days.
Confirmed errors are fixed promptly. Material corrections — anything that changes a result — are noted on the affected page and the "last updated" date is revised.
If we cannot reproduce the issue, we reply explaining what we tested.

Advertising and independence

The site is funded by advertising served through Google AdSense. Advertisers have no input into which calculators we build, what formulas we use, or what our explanations say. Ads are labelled and separated from editorial content.