Supported File Types

The following table lists file types supported as attachments by the InterFAX service. See also System Limitations for unsupported file behaviors.

Note: Attempting to send a file with an extension which is not its native extension, as defined below, will result in a rendering error.

Document Extension File Type MIME type
DOC, DOCX Created by Microsoft Word 97, 2000, XP, 2003, 2007, 2010, 2013, 2016 & 365; Google Docs; Zoho Docs. application/msword, application/vnd.openxmlformats-officedocument.wordprocessingml.document
DOT Created by Microsoft Word 97, 2000, XP, 2003, 2007, 2010, 2013, 2016 & 365. application/msword
PDF Adobe Acrobat (Version 9) application/pdf
TIF Group 3 TIFF, may be in standard or fine resolution **** image/tif
TXT ASCII Plain Text text/plain
XLS, XLSX Microsoft Excel 97, 2000, XP, 2003, 2007, 2010, 2013, 2016 & 365; Google Docs; Zoho Docs
Note: Only active worksheets will be faxed
application/vnd.ms-excel
HTM/HTML*** HTML files Note that HTML is opened and converted to faxes using Internet Explorer v6 (as of June 2013:) v10. text/html
MHT*** MHT web archive files; HTML with embedded images
Note that HTML is opened and converted to faxes using Internet Explorer v6 (as of June 2013:) v10.
message/rfc822
URL Windows URL files
Notes: 1.) The contents of the linked page will be faxed; 2.) HTML is opened and converted to faxes using Internet Explorer v6 (as of June 2013:) v10..
application/internet-shortcut
PPT, PPTX Microsoft PowerPoint 97, 2000, XP, 2003, 2007, 2010, 2013, 2016 & 365; Google Docs; Zoho Docs application/vnd.ms-powerpoint
GIF Non-animated GIF files * image/gif
PNG PNG files image/png
JPG/JPEG JPEG files * image/jpg
PS PostScript application/postscript
RTF Rich Text Format application/rtf
BMP Windows Bitmap * image/bmp
ZIP Any of the above file types may be compressed as a zip file. Multiple files within a single zip file are allowed. application/zip

** For best results use only monochrome (1-bit color, not grayscale) with the following image sizes

*** HTML documents are rendered using MS Internet Explorer, with page margins set to 10.16mm (left, right, top, and bottom)

****Image Sizes

  Standard Resolution Fine Resolution
  Width Height Width Height
A4 1,728 1,169 1,728 2,338
Letter 1,728 1,100 1,728 2,200
Legal 1,728 1,400 1,728 2,800
B4 2,048 1,357 2,048 2,714

Contact us today

Talk to a member of our team about the benefits InterFAX can bring to your organization's communications processes.

Contact us today