Contact
Write to us by email. There is no contact form, because a form would mean sending what you type to a server, and this site is built around not doing that.
Bug reports, format requests, and questions about the privacy policy are all welcome at this address.
Reporting a conversion that went wrong
Please do not attach the file. Describe the tool, the format you started from, the format you wanted, the browser and version you used, and what the page showed you. That is almost always enough to reproduce the problem with a file of our own.
If a file is genuinely needed, we will say so and ask, rather than assuming you want to send it.
Asking for a format
Some formats are missing on purpose. Office documents, OCR, and a few archive formats cannot be converted reliably in a browser, and this project would rather leave them out than send your file to someone else to do it. If you ask for one of those, that is the answer you will get, and it is worth knowing in advance.