Methodology & Data Sources

Every MoneyMath calculator is built on public, citable data from federal and state government sources. This page lists exactly what feeds each tool, when it was last updated, and where you can verify.

Tax rates & IRS figures

• Federal income tax brackets: IRS Revenue Procedure 2025-32 (2026 adjusted figures).
• Self-employment (SE) tax rate: 15.3% (12.4% Social Security + 2.9% Medicare). Social Security capped at the 2026 wage base. Source: IRS SE Tax page.
• Standard mileage rates: Updated annually by IRS. 2026 business = $0.70/mile. Source: IRS Standard Mileage Rates.
• HSA contribution limits: IRS Revenue Procedure 2025-32.
• IRA / Roth contribution limits: IRS Notice 2025-83 for 2026 figures.

Social Security / Medicare

• 2026 Social Security wage base: Confirmed by SSA Fact Sheet (annual October release).
• FICA rates: 6.2% Social Security (each side) + 1.45% Medicare (each side) + 0.9% Additional Medicare Tax above $200k/$250k thresholds.

Wage / benchmark data

• S-Corp Reasonable Salary benchmarks: Bureau of Labor Statistics (BLS) Occupational Employment and Wage Statistics (OEWS). Source: BLS OEWS. Updated annually (May release).

State property tax

• Georgia millage rates: Published by county tax commissioners annually. County-level figures updated each fall when county budgets are finalized.
• Assessment ratio (Georgia): 40% of fair market value (O.C.G.A. § 48-5-7).

AI / LLM pricing

• Model context windows and prices: OpenAI, Anthropic, and Google AI pricing pages, as of the last site update. Prices change often — we review quarterly and on any provider announcement.
• Token counting: Estimated via characters-per-token averages (GPT ~3.8, Claude ~3.6, Gemini ~3.9) for speed. For exact counts, use official tokenizer libraries.

Update cadence

Every calculator page shows a "Last updated" date and a "Reviewed by" attribution. We update:

• Within 48 hours of IRS or SSA rate announcements.
• Every January for new tax-year brackets.
• When a reader-reported correction is verified.

Known limitations

MoneyMath calculators are simplifications. They do not capture every edge case (AMT phase-ins, complex multi-state apportionment, some state-specific deductions, etc.). For final numbers that affect filings or major financial decisions, always pair these results with professional review.