FMF is a filename extension associated with fax document files. FMF files are used by Windows program called FaxMan Jr, a fax integration solution compatible with FaxMan driver.

FMF files store TIFF-formatted data. FMF files are 1728 by 98 pixel (low) or 1728 by 196 pixel (high). FaxMan Jr is capable of importing text data or data from BMP, PCX, DCX, and TIFF files. Several fax file can be combined into a single package. FMF file extension is considered obsolete and is no longer in use.