Find File Extension In PHP

23rd February 2009 - 2 minutes read time

This simple code example uses a combination of strrchr to find the last occurrence of a string and substr to return part of the string in order to find the file extension for a given filename. This is ideal if you want to quickly find a file extension.

$ext = substr(strrchr($fileName, '.'), 1);

This code can be used in the following way.

$fileName = '\path\to\file\afile.wibble';
$ext = substr(strrchr($fileName, '.'), 1);
echo $ext;

The output here is 'wibble';

PHP

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