Calculator Methodology

TrueWealthMetrics calculators are designed for clarity and planning. They use standard finance formulas and transparent assumptions so you can estimate outcomes quickly and compare scenarios.

How our calculators are built

Standard formulas: We use widely taught finance math (amortisation, compound growth, ROI, and budgeting totals).
Clear inputs → clear outputs: Every output is directly derived from the inputs shown on the page.
Conservative defaults: Where a default is needed, we use simple, user-friendly assumptions (for example: monthly compounding).

Common assumptions (important)

To keep calculators fast and easy to understand, most tools make simplified assumptions such as:

Rates stay constant for the full period (interest rates and investment returns can change in real life).
Payments/contributions occur at a regular frequency (monthly is common).
Fees, taxes, account rules, and provider-specific compounding conventions may not be included unless the tool explicitly asks for them.
Results are rounded for readability.

Because of these assumptions, calculator results should be treated as estimates, not guarantees. For personalised advice, consider speaking to a qualified professional.

Rounding & display rules

Currency values are typically rounded to the nearest whole unit (or 2 decimals where appropriate).
Percentages may be rounded to 1–2 decimals.
Tables may truncate long schedules to keep pages fast on mobile.

Validation checks

Before publishing or updating a calculator, we run quick sanity checks such as:

Comparing outputs against known examples (textbook cases and independent calculators).
Testing edge cases (0% rate, short terms, very small/large values).
Verifying that changing one input changes only the expected outputs.

If you notice an issue, please contact us and include the inputs you used so we can reproduce the result: Contact TrueWealthMetrics.

How to interpret results

Use ranges: Try low/medium/high assumptions (for example: 4%, 6%, 8%) and compare.
Focus on trade-offs: The tools are best for comparing scenarios (pay more vs pay minimum, invest early vs later).
Look for sensitivity: If a small change in an input creates a huge change in output, treat the estimate cautiously.

Editorial Policy — how we review and maintain content.
About — what TrueWealthMetrics is and who it is for.
All Calculators — browse the full calculator suite.