How can I get a file's extension in PHP?

This is a question you can read everywhere on the web with various answers: $ext = end(explode('.', $filename)); $ext = substr(strrchr($filename, '.'), 1); $ext = substr($filename, strrpos($filename, '.') + 1); $ext = preg_replace('/^.*\.([^.]+)$/D', '$1', $filename); $exts = split("[/\\.]", $filename); $n = count($exts)-1; $ext = $exts[$n]; etc. However, there is always "the best way".