Contact us
Spotted an error, have a suggestion, or want a calculator we don't have yet? We'd love to hear from you.
Reporting a wrong number
These are the messages we most want. Every calculator is built from a published formula and checked against a worked example, but rates change, rules change, and errors survive review.
Four things let us reproduce it in minutes rather than guess:
- Which calculator — the page address is easiest.
- What you entered — the actual figures, including anything you changed under “More options”.
- What it gave you, and what you expected — both numbers.
- Where your figure comes from — a lender's statement, an IRS page, a textbook. A disagreement is usually a difference in assumptions, and the source is what shows us which.
Suggesting a calculator
Tell us the question you were trying to answer rather than the tool you pictured. “I wanted to know whether overpaying my loan beats saving the money” is more useful than “build an overpayment calculator”, because the first one tells us what the answer has to look like.
What we cannot do
We cannot give advice about your own situation. Not whether to refinance, which account to open, how to file, or what a test result means for you. Those need somebody who knows your circumstances and carries the responsibility for the answer.
What we can do is explain how a calculator reached its number, what it assumed, and where that assumption came from. If the working is wrong, we will fix it and say so.