javascript – Track visitors across different domains using Google Analytics even when they don’t click between the sites


Apparently there are ways to track visitors across different domain using google analytics as described in documentation here and here.

It follows the principle where a visitor click on a link on website1.com and get redirects to website2.com with some additional path params which helps GA track if the visitor is same and GA maintain it’s session.

I have been looking around a lot and couldn’t find a solution on how can I track a visitor which comes on website1.com through ads and then leaves (And/Or open new tab) and immediately/later goes on to website2.com and make some purchase. I am not targeting to maintain session per user but at least I need to know if it’s the same visitor which goes there and converts.

I definately have access to both sites and can put GA tags and javaScripts on both websites.