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EFX File Format

Fax document (Efax Reader)

EFX is a file extension for a document file used with eFax messenger software. EFX stands for EFaX. EFX files contain a fax document that can be sent and received by email, desktop application, and a web interface. 

EFX files can be opened by eFax messenger software. EFX files can also be sent if using the paid version of eFax messenger software.


MIME type: image/efax


Learn more about .EFX files:

Visit eFax web page.

Read more about Faxing at

This was last updated in September 2010
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