I’ve needed to print the currently active WordPress template file and have forgotten it enough times now to finally document it as a post. During development, there’s usually always a time when you’ll want to detect the the template file that’s being called.
I use the following code in my theme/child theme’s header.php file and print it to the screen:
/* show me what the body class will look like */
echo body_class() . "\n";
/* make sure i've got $template */
global $template;
/* print the active template path and filename */
print_r($template);
That’s it. That’s how I print the currently active template file in use for WordPress.