Calculator pages explain what the tool does, how it handles common edge cases, and where its results have limits.
How calculators are reviewed
Each calculator starts with a defined input range, output, and formula. Worked examples are recomputed and checked against the tool. Calculation conventions and sources are documented in the methodology.
How to request a correction
Use Contact and include the page URL, sample inputs, the result you saw, and the result you expected. Do not send personal data or confidential work records.
How changes are recorded
When a correction changes a formula, input rule, or displayed result, record the change and its date in the methodology and rerun the relevant checks. Minor wording and layout updates do not imply a new accuracy review.