About ToolGrym

ToolGrym is a collection of free financial calculators for the decisions most households actually face: taking on a mortgage, paying off debt, building savings, planning for retirement, and understanding what a paycheck is really worth.

What makes these calculators different

Most calculator sites treat the math as a black box. We do the opposite. Every ToolGrym calculator page shows the exact formula it uses, walks through a worked example with real numbers, and links to authoritative sources — the Consumer Financial Protection Bureau, the Federal Reserve, the IRS, and Investor.gov — so you can verify anything we publish.

Under the hood, every calculation is implemented as a pure, tested function. Each formula is pinned to known reference values in an automated test suite that runs before any change goes live. If a calculator says a $300,000 mortgage at 6.5% over 30 years costs $1,896.20 a month, that number has been checked against the standard amortization formula — not copied from another website.

How the site makes money

ToolGrym is free to use and supported by advertising. Ads never change a calculation, never appear above a calculator, and are clearly separated from content. We do not sell financial products, accept payment for recommendations, or share the numbers you type — all calculations run in your browser and are never transmitted to us.

Who writes and reviews the content

Every tool and guide carries a byline: one person writes it, a second person with quantitative credentials independently reviews the math and the claims. You can read about both on their author pages, and our editorial policy describes the review process in detail.

Contact

Found an error, or want a calculator we don't have yet? Email us at [email protected] or use the contact page. Corrections are triaged first and typically shipped within days.