Calculation standards
We prioritize textbook formulas, public standards, and definitions from authoritative organizations. Core inputs remain editable, and calculation logic is isolated so it can be reviewed and tested.
Result interpretation
Guidance comes from published thresholds or explicit conditional rules; it is not presented as generative AI. Custom checklist scores and comparison bands are explicitly heuristic; they are not validated predictions or clinical thresholds.
Quality checks
Release checks combine calculation tests with checks of affected inputs, units, rounding, mobile layout, keyboard access and static pages. Coverage varies by tool and cannot prove every possible result. Financial and health tools include additional limitations.
Updates
When a formula, regulation, or source changes, affected tools are prioritized for review. The sitemap contains only calculator pages that are actually available.