Source hierarchy
For formulas, thresholds, definitions and data, CalcMentor prefers official public agencies, international organizations, standards bodies, central banks, statistical agencies, universities and major public-health or medical institutions.
How competitors are used
Competitor calculators help identify expected inputs, outputs and UX patterns. They are not treated as primary authorities for medical, financial, tax, legal or current-data claims unless their underlying source is separately verified.
Changing data
Currency, inflation, tax, pension and similar data can change. If a reliable data feed is not implemented, the page must say so and use manual input or draft status instead of simulated live data.