About Coastward

Coastward is a free Coast FIRE calculator and a financial-life game. Everything runs in your browser: no accounts, no server, and your numbers never leave your device.

What Coastward is

Coastward helps you explore one question - how much you need invested today so that, with no further contributions, ordinary market growth could carry you to financial independence. The calculator runs deterministic projections and a Monte Carlo simulation. The game turns the same ideas into a financial-life roguelike you can play. Both are free, and both compute entirely on your own machine; the figures you type are never sent to us or to anyone else.

Who makes it

Coastward is built and run by a single independent developer. It publishes under the site's name rather than a personal byline, but there is a real person behind it who reads the mail and fixes the mistakes. If you have a question, a correction, or a suggestion, it goes to one inbox and gets read.

Why you can trust the numbers

Every statistic on this site is one of two things. It is either computed at build time from bundled academic datasets - the Shiller US stock and inflation series, the Damodaran asset-class returns, and the Kenneth R. French data library - or it is clearly labeled as illustrative. Nothing is a fabricated figure dressed up as a derived one. The full methodology, including how the simulation samples history, is public on the How it works page. The Monte Carlo resamples real multi-year blocks of market history, crashes and all, so that the sequence of good and bad years is preserved rather than averaged away.

What Coastward is not

Coastward is an educational tool, not financial advice. It is not a registered investment adviser, it does not know your full situation, and it cannot tell you what to do with your money. Please read the full Disclaimer before acting on anything you see here, and consult a qualified professional for advice tailored to you.

How it is funded

Coastward is free to use. The site may show advertising to cover its costs, and any advertising or affiliate relationship will always be clearly disclosed where it appears. Ads never change how the calculator works or what the numbers say.

Corrections

If you spot an error in a number, an article, or an explanation, tell us and it will be fixed. See the Contact page for how to reach the inbox and what to include in a correction report.