There are several websites which allow you send a free fax online . Some of these websites are:

The fax can be sent to  USA , Canada, though some allow you to send free faxes to other countries.  Most of the free fax services are supported by advertising  and have limitations on the number of pages per fax and number of faxes that can be sent in one day.  The fax can be uploaded as a .doc or pdf  file  or can be entered in text format.