Editorial policy

Accuracy before everything

Content exists to explain a calculation, not to rank, sell, or persuade. If a sentence doesn't help you understand or check a result, it doesn't go on the page.

Formulas are checked against primary or authoritative secondary sources before publication, and sources are linked from the calculator page wherever a specific standard applies.

Plain language

We write for people who are not specialists. Technical terms are defined where they're used, and every formula comes with a variable-by-variable explanation and a worked example.

Review and dating

Every calculator and guide shows the date it was last reviewed. Reviews re-check the formula, the assumptions, the worked example, and the sources. A page that hasn't been reviewed recently says so honestly.

Corrections

Anyone can report an error using the “Report an error” link on any calculator page. Reports are investigated against the cited sources. When we fix something, the correction is reflected in the page's review date.

We would rather withdraw a calculator than publish one we can't stand behind.

No conflicts of interest

This site has no sponsored results, no affiliate-driven ordering, and no lead generation. Calculators are ordered by category and popularity of use, never by payment.