Methodology & data sources
How we build our calculators, where our numbers come from, and how often we update them.
How our calculators work
Every RealMoneyIQ calculator uses standard, published finance formulas — compound interest, amortization, present/future value, tax-bracket marginal math, and safe-withdrawal models. Calculations run entirely in your browser using the assumptions you enter. We do not fit models to proprietary data or produce “personalized” outputs behind a black box.
Where our rates come from
Tax brackets, contribution limits, scheme interest rates and benefit figures are taken directly from official government and regulatory publications for this region:
- Internal Revenue Service (IRS) — Federal income-tax brackets, standard deduction, FICA, retirement contribution limits
- Social Security Administration — Wage base, benefit and COLA figures
- Federal Reserve / FDIC — Savings and deposit-rate context
Each calculator lists the specific sources and the tax year or financial year it reflects, shown in the “Updated” badge and the sources panel beneath the results.
How often we update
We refresh rates whenever the responsible authority publishes changes — annual budgets, quarterly small-savings notifications, and mid-year indexation adjustments. Historic assumptions (such as long-run market returns and inflation) are documented in each calculator's assumptions box so you can change them.
Important limitations
Results are estimates, not guarantees or advice. Real-world outcomes are affected by factors a general calculator cannot capture — your exact filing situation, state/provincial nuances, sequence-of-returns risk, fees, and future rule changes. Always confirm decisions with a licensed professional who knows your full circumstances.