Preferred sources
For formulas, thresholds, definitions and official data, CalcMentor prefers public agencies, international organizations, standards bodies, central banks, statistical agencies, universities and major medical or public-health institutions.
Examples of high-trust sources
Health pages may use sources such as WHO, NHS, CDC, ACOG or MedlinePlus. Unit conversions may use NIST or other standards bodies. Currency and inflation pages may use central banks, Eurostat, national statistical agencies or World Bank data where appropriate.
Source roles
A source can support a formula, a definition, a threshold, a data point, a limitation or a data value. These roles are not interchangeable: a public-health source may support a health threshold, while a standards body may support a unit definition.
How we use product research
We look at common calculator patterns to understand what people expect to enter, what results they need and where calculators often become confusing. Those observations help the page design, but they do not replace official or specialist sources for medical, financial, tax, legal or current-data claims.
Changing information
Some data changes often. Exchange rates, inflation data, tax rates, pension rules and benefit limits require a source and a freshness label. When CalcMentor does not have a reliable data feed, the page uses manual input or clearly states that live data is not included.
When sources conflict
If sources disagree, the page explains the selected method, avoids overclaiming and links to the most relevant authoritative source. High-stakes topics are handled conservatively.
Last reviewed: 2026-05-17