DebtFree Calculators is built and maintained by Cog and Key LLC.
It started with a simple observation: almost nobody is shown the actual cost of the money they borrow. They're shown a monthly payment. The payment is the number that gets negotiated, the number on the sign, the number the finance office asks you for — and it is the one number that can hide everything else.
So these calculators all do the same thing: put your situation next to a better version of it, and show the difference in three numbers — interest saved, time saved, total cost. Once you can read those three, you can read any offer anyone puts in front of you.
What I am, and what I'm not
I'm not a financial advisor, a lender, or a broker. I have no license, no product to sell you, and no relationship with anyone who does. What I have is the ability to build the tool correctly and the willingness to write down exactly what it assumes.
That's a real limit and it's worth stating plainly. These pages can tell you what a loan costs. They can't tell you whether to take it, whether prepaying beats investing for you, or what your particular situation calls for. For those, talk to someone qualified who knows your whole picture.
How the numbers are produced
Every figure on this site is computed by the same engine, in your browser, from the inputs you type. Nothing is estimated by hand, and no number is copied from another site. The math is checked against a set of reference cases you can reproduce in a spreadsheet, and each calculator lists exactly what it assumes and what it leaves out.
Where a page makes a factual claim — how dealer financing is compensated, how credit inquiries are scored — it links to the primary source rather than to another blog post.
How this is paid for
Transparently, and with limits I've written down in advance. The how this site makes money page lists every revenue source I'll accept, every one I won't, and the promises attached to both. The short version: your numbers never leave your browser, and your contact details are never sold to anyone.
Getting in touch
Corrections are genuinely welcome — if a number here is wrong, I want to know before the next person reads it. So is hearing that a page helped, which is most of what keeps this going.