Methodology
How a calculator earns its place in the library
Accuracy is a documented process, not a badge. These are the controls applied to Loan Lyze calculators and their supporting content.
Specify
Document the formula, inputs, exclusions, rounding policy, and authoritative sources before release.
Implement
Keep calculation functions separate from interface and editorial content so their behavior can be tested directly.
Test
Cover representative, boundary, zero-rate, high-rate, short-term, long-term, and invalid cases with reproducible fixtures.
Explain
Describe what the output means, what it excludes, which assumptions matter, and where an official source or professional review is needed.
Validate
Run unit, type, lint, production-build, interaction, mobile, and automated accessibility checks.
Maintain
Version time-sensitive constants, display applicable years and review dates, monitor rule changes, and regression-test corrections.
What automated tests can and cannot establish
Tests can establish that code produces expected results for documented scenarios and remains stable after changes. They cannot make uncertain inputs accurate, reproduce every lender or software convention, determine eligibility, or replace individualized review. Independent qualified review is recommended for consequential decisions and will be disclosed when a named reviewer is engaged.
Time-sensitive rules
Tax, payroll, retirement-limit, federal student-loan, VA, estate, and similar pages identify their supported year or expose the governing value as an input. Always compare the displayed review date with the effective date of a current official source.
See the editorial policy for sourcing and maintenance standards and the corrections policy for error reports.