Sources and citations

Our figures come from primary sources: the agencies that set or publish the numbers, not second-hand summaries. This page names each authority and what it backs. Individual calculators and playbooks also cite their specific sources on the page, and the figure-bearing glossary terms link the exact document behind each number.

Internal Revenue Service (IRS)

Federal income tax brackets, the standard deduction, long-term capital gains rates, the net investment income tax, and retirement contribution limits. Our 2026 figures follow IRS Rev. Proc. 2025-32.

Visit irs.gov

Social Security Administration (SSA)

The Social Security wage base (the annual cap on earnings subject to the 6.2 percent Social Security tax) used in the paycheck and federal income tax calculators.

Visit ssa.gov

U.S. Bureau of Labor Statistics (BLS)

Consumer Price Index data (CPI-U, All Urban Consumers, series CUUR0000SA0) behind the inflation and purchasing-power calculator.

Visit bls.gov

SEC Investor.gov

Plain-language investing basics and the framing behind compounding, dollar-cost averaging, and safe-withdrawal concepts.

Visit investor.gov

Federal Reserve

Consumer credit data (the G.19 release) and the official guide to mortgage refinancing referenced in our debt and mortgage playbooks.

Visit federalreserve.gov

Consumer Financial Protection Bureau (CFPB)

Guidance on paying down debt, how mortgages amortize, prepayment penalties, and auto loans referenced across the debt, mortgage, and auto content.

Visit consumerfinance.gov

Federal Trade Commission (FTC)

Consumer guidance on financing, leasing, and buying a car behind the buy-versus-lease and auto playbooks.

Visit consumer.ftc.gov

Want to see how we turn these into tested calculators? Read how we build and verify and our methodology.