About this document

The financial truth they don't advertise.

Banks spend billions making personal finance confusing. This is a small set of calculators that cut through the noise — for free, with no email and no affiliate redirects.

Founded: 2026
Investors: None
Affiliates: None
Cost to use: $0.00

What Banks Hide exists because banks profit from financial confusion — and most "free" calculators on the internet make the confusion worse, not better. They are ad-delivery systems wearing a calculator's coat. The faster you click through, the more they earn from the lender on the other side.

Every calculator on this site runs real, documented math. Every tool exposes the numbers banks would rather you not see, and lets you compare strategies side by side. No affiliate fees steering your decisions. No paywall hiding the useful parts. No paid placement inside a result. Display ads may sit alongside the calculators — they do not change a single number.

The site is built and maintained by one person. The methodology for every calculation is published on the page of the tool that uses it. If you find a number that's wrong, write to support@whatbankshide.com — corrections are public-record.

Operating principles

Your data stays yours.: Every calculation runs in your browser. We can't see what you type — and we designed it that way.
No friction, ever.: No accounts, no sign-ups, no email gates. The tools work the moment they load.
Every formula exposed.: No black boxes. Every calculator documents its methodology. You can verify the math line by line.
The truth, not a pitch.: We don't take affiliate fees from lenders. The result the calculator gives you is the only thing on the page.

All calculations use standard amortization formulas. We compute month-by-month schedules — no shortcuts or approximations — and use integer cents internally to avoid floating-point drift on long horizons.

Code for every calculator is published under the project repository. If a number on this site disagrees with a number on a lender's statement, the lender's is the contractual one; ours is the educational comparison.

Disclaimer

These calculators provide estimates based on the inputs you supply. They are educational tools, not financial advice. Actual loan terms, tax implications, and investment returns may differ. Consult a licensed financial professional for decisions specific to your situation.