Editorial standards

WealthCompounds is an independent education project. Articles and calculators are written for this site and revised when a figure or a rule of thumb goes stale. The point of a page is to show the math and name the assumption, not to send you to a product.

How the calculators work

Compound interest is credited on the schedule you pick, after that period's contributions. The FIRE number is annual spending divided by a withdrawal rate you choose. The default rate is 4%, which is a research shorthand for a long retirement, not a promise.

Years to a target use the future value of a level monthly contribution at a constant return. The savings-rate chart starts from zero, treats the unsaved share of income as spending, and sizes the portfolio at 25 times that spending when the withdrawal rate is 4%.

Coast FIRE walks backward from a capitalized retirement portfolio. Social Security and long-running side income reduce that portfolio. Partial withdrawals before retirement raise the amount you need today. Real mode uses a real return and today's dollars. Nominal mode inflates the cash flows and uses the nominal return. Both are labeled.

The 401(k) tool applies the employee deferral cap and a simple match: a match rate times the deferral that falls inside a percent-of-pay window. The drawdown tool withdraws an inflation-adjusted amount each month and applies a constant nominal return. It will look calm in a way real retirements are not, because it has no bad decade.

Sources

Contribution limits are the 2026 figures from IRS news release IR-2025-111 (November 13, 2025), Notice 2025-67. Net-worth medians are the 2022 Survey of Consumer Finances as published in the Federal Reserve Bulletin in October 2023, in 2022 dollars. Other percentiles on the net-worth page are approximations and are labeled as such.

The savings-by-age multiples are Fidelity's published retirement-savings guidelines (about 1× salary by 30, 3× by 40, 6× by 50, and 10× by 67). They are a benchmark with their own assumptions about retirement age and lifestyle, not a grade.

The 4% reference is William Bengen's 1994 withdrawal research and the later Trinity study. Those studies used historical U.S. portfolios over fixed horizons. They do not know your fees, taxes, or spending.

Corrections

Limits, medians, and formulas are checked when a page is edited. If a number is wrong, the page should be fixed and the date on legal pages moved when the policy itself changes. This version of the site does not yet publish a corrections inbox. Until it does, the change belongs in the page, not in a promise to reply.

Independence

WealthCompounds does not take payment to feature a broker, a fund, or a credit card. Display ads, if AdSense serves them, are separate from the sentence that explains a formula. The workbooks are our own worksheets. A buy button is a Stripe Payment Link for that PDF. After payment, the file is sent as a private download link, not published on the site. It is not a recommendation to purchase, and the calculator result does not change if you buy one.

Nothing here is personalized advice. Tax law, plan documents, and benefits change. The account-order page is a general teaching sequence with the exceptions written on it.