Contact
Questions and error reports go to the board. No sign-up is needed, and posts are read by the site operator.
The board interface is in Korean. Posts written in English are read and answered all the same.
What is useful to include
- A calculation looks wrong — which calculator, what you entered, and what came out. With the input values the same case can be reproduced exactly.
- Data differs from reality — the complex name or page address, along with the figure you believe is correct.
- A statute or rate has changed — the amended provision or notice, so it can be applied with a stated effective date.
- A topic you would like covered — a calculator or explanation you needed and could not find.
- Quotation or redistribution — the scope and purpose you have in mind.
Posts can be private
Tick private when posting and the body is visible only to the browser that wrote it and to the site operator. Use it for anything you would rather not publish.
The board does not collect an email address or phone number. Replies are posted as a comment on the same thread, so check back from the browser you posted with. Do not include personal information; see the Privacy Policy for what is stored.
About replies
Reports are checked against the primary source before anything changes. That can take time, and not every message will receive a reply.
Changes that alter a calculation result are recorded with their date in the change history at the bottom of each calculator, so you can see when a reported issue has been applied.
See About for what this site is, or Terms of Use for the conditions of use.