Duplicate content refers to situations where identical or very similar content is found on multiple different URLs on the internet.
This can occur both across domains and within the same website and can create challenges for search engines like Google as they have difficulty identifying which version to display in search results.
From an SEO perspective, duplicate content can have a negative effect on a page’s visibility and ranking in Google, so it’s important to understand what duplicate content is and how to avoid it.
What is duplicate content?
Duplicate content can be classified as either external or internal:
External duplicate content: When the same or very similar content is published on several different websites. Examples include product descriptions reused by different webshops or articles shared by several news outlets.
Internal duplicate content: When the same content is found on different URLs on the same website. This can often occur due to technical issues, such as parameter management in URLs, page sorting, or session IDs, which can lead to search engines crawling and indexing multiple versions of the same page.
Examples of duplicate content include:
- Copied product descriptions across product categories
- Printer-friendly pages that are identical to their regular versions
- Sorting and filtering pages in webshops that generate identical product lists with different URL parameters
- Multiple versions of the same page for different geographical regions, but without unique content.
Why is duplicate content problematic?
Duplicate content can confuse search engines as they have to decide which version of the page is most relevant to the user. If the search engine can’t make a clear decision, it can lead to:
Competition between pages: Multiple pages with the same content compete for the same keywords and search intent, which can result in lower rankings for all pages.
Cannibalized search results: Duplicate content can mean that multiple pages from the same website are displayed for a given search, which can create confusion and reduce the relevance of the search results displayed.
Inefficient crawl budget: Search engines spend time and resources indexing and analyzing duplicate pages, which can reduce the amount of new or important pages that are crawled and indexed. (Read more about crawl budget here)
Lost link value: If external websites link to multiple versions of the same content, link authority can be distributed between them, weakening the overall SEO value.
How does duplicate content occur?
There are many reasons why duplicate content occurs. Here are some of the most common:
CMS structures: Content Management Systems (CMS) can often create duplicate pages automatically. For example, a page may appear at both /productname and /categoryname/productname.
URL parameters: Sorting and filtering in URL parameters can create many versions of the same page. Examples might be ?sort=price or ?filter=color.
WWW and non-WWW or HTTP and HTTPS: If both the www and non-www versions of a website are available without a redirect, this can lead to search engines seeing them as separate pages. You can read more about this here.
Printer-friendly versions: Many websites offer printer-friendly versions of their pages, which are often not marked up correctly and therefore get indexed as duplicate content.
How to avoid and deal with duplicate content?
There are several methods for avoiding and dealing with duplicate content:
Implement Canonical Tags
By using rel=“canonical”-tagget you can specify the preferred version of a page. This helps search engines understand which page should be prioritized and considered the original.
Use 301 redirects
A 301 redirect can be used to redirect users and search engines to the preferred page version, which can consolidate duplicate content and transfer link value.
Set up the correct structure for URL parameters
For webshops and other websites with complex navigation options, it can help to use tools like Google Search Console to manage URL parameters and avoid indexing identical pages.
Consider blocking pages via robots.txt or Noindex
If certain versions of the pages are not needed in search results, you can choose to block them with robots.txt or add noindex in their meta tags to avoid indexing.
Create unique content
One of the most effective solutions against duplicate content is to create unique texts and descriptions, especially if you are working with product descriptions or content that is also used by other websites.
How does duplicate content affect SEO?
Duplicate content can directly negatively impact SEO efforts by:
- Reduce the visibility of important pages in search results
- Creating confusion among users and search engines
- Make search engines spend resources on irrelevant pages, which can reduce crawl budget
To avoid these drawbacks, it is important to have a handle on technical SEO, including the use of canonical tags and 301 redirects.
Dealing with duplicate content is crucial if you want to succeed with your SEO strategy. By ensuring that all pages are unique and easily understandable by both search engines and users, you can increase visibility and avoid technical issues and consequences.
If you would like help checking whether your website is affected by duplicate content, you are always welcome to contact one of our SEO consultants.
