Session identifiers in URLs

What is wrong

Session identifiers are unique codes that websites sometimes add to URLs to track individual visitors. When your site creates URLs like `example.com/page?sessionid=abc123def456`, each visitor gets a different code in the address bar, even though they're looking at the same page.

Why it costs you

Google treats these different URLs as separate pages even when the content is identical. This wastes Google's crawl budget—the time it spends visiting your site—because it has to crawl multiple versions of the same page. More problematically, it can fragment your rankings and backlinks across these variations instead of concentrating them on a single URL, which weakens your search visibility.

How to fix it

Move session tracking out of the URL and into a cookie instead. Cookies work the same way for your website but don't create multiple URL variations. If you must use URL parameters, set them as session parameters in Google Search Console (now Google Search Console settings) and use the `rel="canonical"` tag in your page template to point Google towards the preferred version without the session code.