A good way to think about it: the Alternative Format Tool is for getting a document into a usable format quickly, whether for yourself or for a student who needs audio or a different file type. The Remediator is for staff and faculty who are responsible for making documents publicly available or posting them to a course and need those files to meet accessibility and compliance standards.
If you are posting PDFs to a website, uploading course materials, or working through a backlog of documents that need to meet ADA Title II requirements, the Remediator is the right tool for that work. For questions about which tool fits your situation, contact the EdTech team.