How to tell Google to ignore URL parameters and forget about any already crawled?

Question

Is there any way we can delete Google URL Parameters? I know in webmaster tools that there is no option to delete the URL parameters that were crawled by Google, but is their any other way we can take them out of the Google search results?

We had no URL parameters in WMT showing last month and we had a good amount of organic traffic to the website. After few changes on SEO pages, related to rel="canonical" Google has crawled about 20 URL Parameters automatically in the last month. Each URL parameter has around 7,012,505 monitored URLs. We have lost around 50% of the organic traffic.

We made some changes to edit URL parameters, but so far that has not had any effect. We are looking for a way to tell Google to ignore these parameters and forget about all the URLs that it already crawled with them.

Answer 1

You need to do two things:

1. Implement redirects for these URL parameters or make sure any page with the parameters has a rel=canonical to remove them.
2. Set the URL parameters in Google Webmaster Tools under "Crawl" -> "URL Parameters" -> "Configure URL Parameters". Each parameter should be set to "Doesn't effect the page content (eg. tracks usage)" This will cause Googlebot to stop crawling the pages that have the parameters and instead choose one representative URL (likely the version without the parameter).

After you make these changes I would expect it to take at least two weeks for Google to drop the URLs with the parameters from the search index. With seven million URLs to deal with, it could take Googlebot significantly longer than that. If you have a small site, it could take Googlebot months to get around to purging that many URLs from the index.