FileInfo.com


.CER File Extension


File Type Internet Security Certificate
File Format File
Common? No
File Description Security file provided by a third party such as VeriSign or Thwate that confirms the authenticity of a Web site; installed on a Web server (such as Apache or Windows Advanced Server) to authenticate the validity of a certain website hosted on the server; represented by a lock icon near the edge of a browser window when accessing a secure site (beginning with "https://").

The information from a secure certificate can be viewed by double-clicking the lock icon located near the bottom of a browser window in Internet Explorer or Firefox; to view the certificate information in Safari, click the lock icon near the top-right corner of a browser window.
Program(s) that open cer files Mac / Windows: Viewable in a Web browser

Information from FileInfo.com - The File Extensions Resource.
http://www.fileinfo.com/extension/cer