Get previously visited page ID

I would like to get the ID (or permalink) of the page the visitor visited just before visiting the current page – in other words the ID of the last page in the browser history.

Can this be done? Any idea how to do it?

Break this down into two parts:

First, we create a variable that stores that last-visited page URL, like this:

$prev_url = isset($_SERVER['HTTP_REFERER']) ? $_SERVER['HTTP_REFERER'] : '';

Then, you could either use substr and strpos to trim down everything between ?= and the / after the ID number. like this:

$prev_url="http://www.yoursite.com/?p=123";
$id_block = substr($prev_url, strpos($prev_url, "?p=")+1);
$id = substr($id_block, 0, strpos($id_block, "https://wordpress.stackexchange.com/"));

.. Or, you could use jQuery/Javascript to achieve the same.

I haven’t tested this but it should work – let me know how it does!
Good luck 😉