Methodology

Principles that guide how Calcafy calculators are designed, tested, and maintained.

Formula accuracy

Calculation logic is implemented as pure functions separate from UI components. This makes formulas easier to test, review, and reuse.

Testing

Core formulas are covered by unit tests for normal inputs, edge cases, invalid values, and rounding behavior. Registry validation helps prevent broken routes and metadata issues.

Assumptions and limitations

Calculators should state what is included and excluded. Financial tools note that results are estimates. Health-related tools avoid diagnosis or personalized medical claims.

Updates and corrections

When a formula, default, or explanation changes, the affected calculator entry should be reviewed and its last-reviewed date updated. Issues can be reported through the contact page.

Keyword-driven expansion

New calculators are prioritized using keyword research, editorial review, and category strategy. Keywords do not automatically become pages; each candidate is evaluated for intent, usefulness, and cannibalization risk.