Contact us
Questions, corrections and tool suggestions are all welcome. The fastest route is email — we read everything and reply to anything that needs a reply.
Send a message
This form composes an email in your own mail client. Nothing is submitted to a server from this page, in keeping with how the rest of the site works.
Before you write
Reporting a wrong result
Please include the exact values you entered, the result you got and the result you expected. Many reported “errors” turn out to be a convention difference — a flat versus reducing interest rate, an inclusive versus exclusive day count — and knowing your inputs lets us tell the two apart quickly.
Suggesting a tool
Tell us what you are actually trying to do rather than just naming a tool. The most useful suggestions describe the task, which often reveals that a better tool than the one requested would solve it.
Advertising concerns
If an advert is obscuring content, appearing inside a tool’s controls or looking like part of the interface, we want to know. Include your device and browser so we can reproduce it. Our placement rules are described on the about page.
Privacy questions
The privacy policy covers what is and is not collected. If something there is unclear, ask — vague privacy writing is a bug like any other.