How Does Duplicate Content Affect SEO?

Megan Watts - Digital Marketing Executive

Megan Watts

11th December 2020

There is often a dark cloud casting a shadow over duplicate content, but how much do you really know about how it affects SEO? It is not best practice to have either internal or external duplicate content if you can help it, but sometimes we don’t know if we have duplicate content or what effect this can have on our rankings and SEO goals. Therefore, in this article we take a look at what duplicate content is, how it affects SEO, how to check for it and how to combat it if your site has been affected. 

What Is Duplicate Content? 

Google defines duplicate content as “substantive blocks of content within or across domains that either completely match other content or are appreciably similar.”

To put things simply, duplicate content is content that appears online at more than one web address. 

Sometimes duplicate content is unavoidable or accepted, such as store items being shown or linked via multiple distinct URLs or even just through human error. Other times, it can be due to plagiarism.

What Causes Duplicate Content?

Duplicate content can be present on the web for many reasons. It is easy to assume that they are all instances of plagiarism, with one website copying text from another website, but often there is a more technical reason. It doesn’t feel natural for many people to copy content without making it clear what the original source of the information is. 

There are two types of duplicate content:

  • Internal duplicate content is when one domain creates duplicate content through multiple internal URLs (on the same website).
  • External duplicate content occurs when two or more different domains have the same page copy indexed by a search engine.

Why Does Duplicate Content Matter?

Duplicate content can present some issues for both search engines and site owners. 

Here are some issues for search engines:

  • If there are multiple URLs with the same content, it can be unclear which version(s) should be included or excluded from search engine indices.
  • It can cause problems when directing link metrics such as trust, authority, anchor text and link equity. 
  • Search engines may not know which version of the content to rank in search query results.

There are also a couple of issues for site owners:

  • Search engines rarely show multiple versions of the same content. This means that the search engine has to choose which version of the content is most likely to be the best result. Ultimately, this dilutes the visibility of each piece of content, which is not good for either domain.
  • Link equity can be also be further diluted because other sites have to choose between the duplicates as well. Instead of all inbound links pointing to one piece of content, they link to multiple pieces, spreading the link equity among the duplicates. This may not sound like much of an issue, however, because inbound links are a ranking factor, this can then impact the search visibility of a piece of content.

How Does Duplicate Content Affect SEO?

Knowing that duplicate content can create issues for your site and how it ranks on search engines, your thought process likely leads you to question how your SEO may be affected. 

There is no official penalty for duplicate content, but loss of ranking for your web pages is likely. As Google has to choose which of the duplicate pages should rank in the top results, regardless of who created the original content, there is a high possibility that your content may not rank. 

This is not only an issue when looking to rank against competitor websites. If your site has a lot of duplicate or similar content, your site may suffer in terms of SEO. 

Here are a couple of reasons why internal duplicate content can be an issue:

  1. Less Organic Traffic: As mentioned above, Google doesn’t want to rank pages that uses content that’s copied from other pages in Google’s index. So if you have multiple pages on your site with similar content, Google will not be able to identify which one is the original. The knock-on effect this has is that each of these pages will struggle to rank.
  2. Fewer Indexed Pages: If you are a retailer with an ecommerce site, it is important to be aware that Google doesn’t just downrank duplicate content, but it may also not index it. As ecommerce sites tend to have lots of product pages, this can be a problem when it comes to ranking for each page. If you have pages that aren’t getting indexed, it is likely that your crawl budget is getting wasted on said duplicate content.

Continuing on from this, it is also worth mentioning that another issue that retailers can face when it comes to duplicate content is the ability to create unique product descriptions. 

Understandably, creating unique product descriptions is challenging for many eCommerce companies, as it can take a lot of time to write original descriptions for each product on a website, especially if you have thousands of different products.

However, if you want to rank for each specific product, say a “Schneider Protected LED Bulb”, then you will need to differentiate your product page for this product from all the other websites offering that exact product in order to outperform competitors. 

How Do You Know If You Are Suffering From Duplicate Content?

If you have web pages that are declining in search rankings, it is a good idea to check for duplicate content, but how do you go about doing this? 
One simple way that you can check for duplicate content on your site is to do an exact-match search. 

If you copy a few sentences of text from one of your suffering web pages, put it in quotation marks and then search for it in Google, you should be able to see if any other sites are using this exact wording. 

By using quotation marks, you’re telling Google that you want results that return that exact text. If multiple results show up, then it is likely that case that someone has copied your content.

How To Combat Duplicate Content

If you can see that there are duplicates of some content you have created, whether this has been done intentionally or not, there are some steps that you can take to address this and to ensure that visitors see the content you want them to. Some of these solutions are a little technical, so it may be worth contacting a web developer to help with this: 

Here are a few ideas:

  • Use 301s: If you've restructured your site, use 301 redirects in your .htaccess file to help redirect users, Googlebot, and other spiders. 
  • Be consistent with internal linking: this can be achieved by keeping your page URLs consistent in format when you publish new pages. 
  • Minimise boilerplate repetition: Instead of including lengthy copyright text on the bottom of every page, include a very brief summary and then link to a page with more details to prevent repeated pieces of content on each page.
  • Avoid publishing empty pages: Users don't like seeing placeholder pages that don’t yet have any real content, so it’s best to avoid this. 
  • Minimise similar content: If you have many pages that are similar, consider expanding each page or consolidating the pages into one.
  • Use canonical tags: If you have multiple pages that are identical, you can use canonicalization to tell search engines which version of the URL you would like to appear in search results.

Need Some Support With Your Site?

Google has systems in place to deal with small amounts of duplicate or boilerplate content, so this is less of a worry than if you have noticed problems with entire pages being duplicated on your site, or if you suspect plagiarism. 

It is more important to be aware of and keep an eye out for technical SEO mishaps on large site with lots of pages. This ahrefs article is very informative if you’d like to know more in-depth information about this. Additionally, if you would like to learn more about the different aspects of SEO, such as off-site, on-page and technical SEO, keep exploring our blog

If you would like help with any aspect of your SEO, then don’t hesitate to get in touch with SilverDisc.

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