Calculator methodology
Each calculator states its inputs, formula, assumptions and important exclusions. Financial formulas are independently recalculated before publication and tested against representative edge cases.
Live and time-sensitive data
When a tool uses a live value, the page identifies the source and freshness. A value that cannot be verified is not presented as current.
Corrections
Material calculation or factual errors are corrected promptly. The affected page should explain the correction when it changes how a result is interpreted.