Outputs the file extension of the filename indicated by parameter {{{1}}}. In the File: namespace, this parameter defaults to {{PAGENAME}}. In all other namespaces, the default output is an empty string. Any uppercase letters in the file extension are changed to lowercase.

Usage

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Input Output Notes
{{file extension}} (empty string output because current page is in the Template: namespace)
{{file extension|Makefile}} (empty string output because specified filename has no extension)
{{file extension|I-35.svg}} svg Input filename is acceptable with or without File: namespace prefix.
{{file extension|File:George H. Sharpe.jpg}} jpg
{{file extension|UNMSM logo1.PNG}} png Uppercase is changed to lowercase
{{file extension|Wikimedia Logo.jpeg}} jpeg jpeg is not changed to jpg