In the web world, Google is undoubtedly one of the most widely used search engines. However, there is a flipside to it. It is known as Google’s supplemental index. It is primarily a backup database of pages from the web. If you are unable to find a sufficient supply of relevant pages in its primary or main index, then it will show some pages taken from the supplemental index.

The main index can be denoted as the place you want to be in and supplemental index in this respect would mean the place you do not want be in. It is easy to identify a supplemental listing. For instance, you will simply need to locate the phrase, “Supplemental Result” that will appear in green text situated in the last line of your Google listing.

There are a few possible reasons why you may end up in the section of supplemental index.
They may be enlisted as the following:

1. The page may be buried: There are certain orphaned pages which have a high possibility of becoming supplemental. These pages are such that can be reached only by an intensive crawl of your website’s internal links or some pages that can never be reached.
2. Content may be duplicate: There are some pages that have content simply copied from others. This leads the site to be sent in the supplemental index.
3. Link profile may be weak overall: There are certain websites where the algorithms have a relatively low amount of trust in the outbound links or incoming links of such sites. This leads to them being linked to spammy areas on the web and further sending them to the supplemental index section.
4. Multiple parameters in the URL: Sometimes, there is an excess amount of variables in the Uniform Resource Locator or URL. This leads to additional piling up of pages in the section of the supplemental index.

There are certain possible ways that can enable you to get your web pages out of the section of the supplemental index.
They are as follows:

1. Try to develop your internal linking: You can prepare a site map that will essentially include proper links to all the pages of your website. This will ensure that pages do not get detached or orphaned.
2. Find out if you are victim of theft: There is always a possibility of someone stealing your content and Google might even rank the stolen content rather than yours on the other website. You can use services like Copyscape in order to check for theft of content.
3. Improve upon the architecture of your website: If your website contains certain pages that are a few levels deep that are either away or below the home page, you can re-do the structure so that the pages do not get buried. This will enable the crawler to reach every page of your site.
4. Do away with issues on duplicate content: Ensure that the meta description tags and page titles are unique. It is permissible to have a common site menu, footer, and header on the pages of your website as long as the pages have sufficiently unique material to offset the common content.
5. Renovate the profile of your links: The links that you use affects the level of faith that Google provides you with. If Google has less amount of faith in you, then it will entail more supplemental pages.

Apart from the above mentioned methods, you can also mend your URLS, improve the material on the pages of the supplemental index, rename all the pages on the supplemental index with a different URL and link to the nascent pages significantly on your website, and inform Google about exactly what is happening.

You can also take three primary steps in order to conveniently get your website’s page out of the section of supplemental index and keep it out. Firstly, you can submit a site map directly to Google. Secondly, you can utilize the presence of backlinks. Finally, you can check your website for any form of duplicate content by using Copyscape.

However, at times, even after the problem is solved, it might still take some amount of time for most of the supplementals to get completely erased. Nevertheless, if the quantity of supplementals does not increase, your content is original, and your site’s rank is good by Google then you need not worry too much about supplementals.