About WealthCompounds

Personal-finance arithmetic is short. The tools around it are often not. WealthCompounds runs the arithmetic in your browser and writes down the assumptions next to the result.

The calculators cover compound interest, a FIRE number, Coast FIRE with Social Security and side income, a 401(k) match, how long a portfolio lasts under a constant return, and a savings-rate chart. Guides next to them explain the words. None of it is a plan for your household.

What runs where

The pages are static HTML. A small script updates a calculator when you change an input. Your numbers stay in the page. They are not sent to WealthCompounds. There is also a public JSON endpoint, POST /api/coast-fire, for the same Coast FIRE math. The website does not call it for you.

The site can show Google Analytics and Google AdSense. Those scripts load after you scroll, click, or press a key, so they are not part of the first paint. The privacy page says what they do.

Workbooks

Two optional PDFs sit beside the free calculators: a Coast FIRE Plan and a Money Autopilot Workbook. They are worksheets, not advice and not a managed account. Buy buttons appear when a Stripe Payment Link is configured. Until then the products page says coming soon. A paid checkout returns here for a download link and emails another copy. The files are not on a public page.

Who it is for

• Someone who wants to see why starting earlier changes the picture, using their own monthly amount.
• Someone mid-career who wants a FIRE number and a Coast number with the assumptions written out.
• A parent or teacher who wants a chart of compounding that does not ask for an account.

Figures are ballpark. Taxes, fees, a changing savings rate, and a bad sequence of returns are not in a constant-rate calculator. Read the editorial standards for how pages are written and corrected.