Our calculation standard

Transparent inputs, reproducible formulas, honest limits.

The calculation engine is implemented separately from the interface so known examples and edge cases can be tested directly. Each tool explains its assumptions and limits. Automated checks support those explanations but do not certify personal suitability or every possible input.

Decision-first calculations

Affordability tools reserve essential living expenses, existing debt, user-selected saving, ownership costs, and safety margins before estimating a payment or price. Loan tools use standard fixed-rate amortisation unless the page states otherwise. Growth tools clearly separate contributions from estimated returns.

Reproduce our guide examples

These hypothetical figures use a single currency, monthly payments and no fees. They are not market-rate quotations.

• Emergency fund: expenses 3,600, current savings 1,200, target one month and contribution 450 → six end-of-month deposits at zero growth.
• Home: income 6,000; living costs 2,500; debt 300; saving 500; margin 5%; ownership costs 400; deposit 40,000; 6% nominal annual rate; 30 years → price approximately 373,583. At 8%, approximately 312,567.
• Debt: balance 4,000 at a fixed 18% nominal annual rate; payment 100 → 62 months and approximately 2,154.49 interest. Payment 600 → eight months and approximately 246.27 interest.

The guide-example automated tests check these outputs against the shared calculation functions. See the guides for context and limitations. This is internal testing, not independent financial certification.

Testing scope

Automated checks cover known examples, selected zero-rate and payment boundaries, and budget-transfer mappings. Browser checks cover selected connected journeys. This does not establish exhaustive cross-browser, accessibility, tax, lending or investment-model compliance. Report errors through the contact below.

Source hierarchy

We prefer regulators, government consumer-finance agencies, legislation or official rules, and international financial-education bodies. Commercial sources may explain a product, but they do not replace an official rule. Guides display the main sources used and identify facts that must be checked locally.

What an answer does not mean

Results are educational estimates—not credit approval, product suitability, legal interpretation, tax advice, or an investment recommendation. Fees, taxes, inflation, product terms, regulation, provider rules, and personal circumstances can materially change an outcome.

Corrections and review

Read the editorial policy. To report a concern, send the exact page, inputs, expected result, and supporting source to support@tritanai.com.