XFDF is a file format compatible with Adobe Acrobat and other PDF readers. XFDF files used XML format for storing data such as form encoding and adnotations that can be saved and imported/exported into PDF and viewed with, for example, Acrobat Reader.

Adobe XML solution is typically used in business environments and while working with large amount of data. XFDF file (and its older sibling FDF) is not a stand-alone document, but a support file that contains data for related PDF files and thus has limited use.