Calculator Methodology

Calculators should use established formulas, standard conversion factors, or clearly documented assumptions. When a topic has multiple accepted methods, the page should explain which method is used and why that method is appropriate for general estimates.

Results are rounded for readability. Financial calculators generally display currency to cents or whole dollars depending on the result. Measurement calculators may use decimal precision that is practical for the task. Rounding can cause small differences from manual calculations or other calculators.

Calculator pages should explain major assumptions near the calculator or in the methodology content. Finance and health calculators include visible disclaimers because they are estimates, not professional advice.

Preferred sources include official documentation, academic references, government publications, standards bodies, and primary sources. For reader-reported corrections, the page should be checked against a reliable source before changing formulas or assumptions.

The broader sourcing and correction process is described in the editorial policy.

Implementation updates should be checked with local build output, rendered page source, route responses, formula spot checks, and page interaction testing when applicable. Reviewer names or credentials should appear publicly only when they are real and explicitly approved.