Trust and transparency

Corrections policy

Calculation defects and materially misleading explanations require a visible, testable correction process. This page explains how to report them without sharing sensitive financial information.

Report a correction

Send non-sensitive correction reports to [email protected] with “Mortgage Rate Impact Lab correction” in the subject line. This is the monitored project channel for calculation, content, accessibility, privacy, and security reports.

Do not send income, debt, credit details, account credentials, Social Security numbers, property addresses, loan documents, or other sensitive financial or personal information through a public issue, social post, or unverified address.

Report scope

The channel accepts focused reports about:

  • Calculation results that do not match the published formula or source vectors.
  • Incorrect descriptions of included costs, note rate, APR, amortization, or payoff timing.
  • Stale or broken primary-source links.
  • Accessibility barriers that prevent using a calculator or understanding a result.
  • Privacy or security behavior that differs from the published notice.

A useful calculation report should contain only non-sensitive test values, the calculator URL, expected result, observed result, browser version, and enough steps to reproduce the problem.

Investigation process

  1. Preserve. Record the report, affected version, formula version, source, and reproducible test case.
  2. Triage. Separate material calculation or safety errors from content errors, accessibility defects, and suggestions.
  3. Reproduce. Confirm behavior using an isolated test and compare it with the documented formula and primary source.
  4. Contain. For a material error, stop release or indexing and add a visible warning or disable the affected result until corrected.
  5. Correct. Change the narrowest responsible code or content and add a regression test.
  6. Review. Repeat engineering validation and any professional or legal review affected by the change.
  7. Disclose. Publish a dated correction record explaining what changed, what users were affected, and whether earlier results should be recalculated.

Severity and response targets

This small public beta does not guarantee a response time. Reports are triaged by severity:

Planned correction severity categories
SeverityExamplesRequired action
CriticalMaterially wrong payment, payoff, balance, or privacy behavior.Block release or affected output, investigate immediately, and require documented revalidation.
HighMisleading financial explanation, missing material limitation, or inaccessible result.Prioritize a tested correction and reviewer check before the next release.
RoutineBroken source, typo, presentation issue, or non-material clarity problem.Correct in the normal release process and record if user interpretation could change.

Correction record requirements

A public change record must identify the date, affected page or engine version, plain-language issue, correction, verification performed, and recalculation guidance. It must not expose a reporter’s identity or report contents without explicit, informed permission.

See contact and safe-reporting guidance.