Privacy

The short version: what you type into a calculator on this site is saved only in your own browser, on your own computer. Nothing is sent to us, because there’s no “us” on the other end of it — there’s no account, no database, and no server that ever sees your numbers. This page explains exactly how, and how to verify it yourself rather than take our word for it.

Where your data actually lives

When you edit an input on a tool — a mortgage rate, a household expense, a retirement age — that value is held in your browser’s memory, and a moment later it’s written to your browser’s local storage: a small, private data store built into every browser, scoped to this one site, and physically located on your device. It is not a cookie, it is not sent with page requests, and it is not visible to any server — including ours. Closing the tab doesn’t lose it; the point of saving locally is that it’s there again next time you open the same tool, on the same device.

You can see exactly what’s stored, and delete it

Open Saved data (linked from the header on every page) to see a plain list of everything this site has saved in your browser right now — which tool, and when it was last saved — with a delete button next to each one, and a “clear everything” option. Nothing about this list is hidden from you or requires digging through browser settings to find.

Turning saving off

The Save data locally toggle in the header controls saving, site-wide. Turn it off and: nothing new gets written to local storage, nothing already saved gets loaded back in (a tool starts fresh, as if you’d never used it before), and anything you type while it’s off is discarded the moment you turn it back on — the same way closing a real private-browsing window discards everything in it. It’s meant for a shared or public computer, or simply not wanting a draft to stick around.

What does touch a server

One thing on this site is not purely local: a small proxy that serves public reference data — current tax brackets and standard deduction amounts — used by a couple of the lessons. It’s the same, non-personal data anyone would get regardless of who’s asking, and it never includes anything you’ve typed into a calculator. Every other calculation runs entirely in your browser.

No accounts, no tracking, nothing sold

There’s nothing to sign up for, so there’s no password, no email address, and no profile tied to you. We don’t run analytics that follow you across the site, there are no ads, and there’s nothing for sale here that your data could be used to target. See About & methodology for more on what this site is and isn’t.

Verify it yourself

You don’t have to take this page’s word for it. Your browser’s developer tools (Application or Storage tab) let you inspect local storage directly and see the same entries the Saved data page shows you, in the browser’s own raw view. And your network tab will show exactly which requests this site makes as you use it — there’s nothing to hide there either.