- urldecode: documentation ( source)
<?php
echo urldecode("http://free-onlineproxy.com/browse.php?u=http%3A%2F%2Fleave.to%2F%3Furl%3Dhttp%3A%2F%2Ffree-onlineproxy.com%2Fbrowse.php%3Fu%3Dhttp%253A%252F%252Flinkcrypt.ws%252Fdir%252Fe3673m67liy097y%26b%3D4&b=4");