Cross-Domain Canonicals Are NOT For Internationalization (Use Hreflang) | Martech Zone

A cross-domain canonical tag is a specific application of the rel="canonical" link element used in SEO, but it extends across different domains. This tag is crucial when managing identical or highly similar content across multiple websites.

When to Use a Cross-Domain Canonical Tag:

  1. Managing Duplicate Content Across Different Domains: If you have the same content published on multiple websites (different domains), a cross-domain canonical tag helps search engines understand which version is the master or preferred content to index. For instance, if you syndicate your blog posts to other sites, using a cross-domain canonical tag to the original post on your primary website tells search engines where the original, preferred content is.
  2. Consolidating Link Equity: In scenarios where the same content exists on multiple domains, cross-domain canonicals can help consolidate link equity (the value passed through hyperlinks from one page to another). Without canonical tags, the link equity could be split across these domains, diluting the SEO value. Specifying a canonical URL ensures that all the SEO benefits, like backlinks and rank authority, are attributed to the chosen URL, regardless of which domain receives the link.
  3. Migrating Content to a New Domain: If you’re moving content from one domain to another (like during a site redesign or rebranding), cross-domain canonicals can be used temporarily to pass the SEO value from the old pages to the new ones until search engines have fully indexed the new domain.

In Search Engine Optimization (SEO) for international websites (I18N), it’s essential to discern between various techniques and their appropriate applications. Specifically, understanding the use and differences between hreflang and canonical tags is vital for effectively optimizing international sites.

HubSpot released an ebook titled 50 SEO & Website Tips for the International Marketer. While HubSpot is a trusted source and many agencies, including ours, partner with them, a particular tip in this ebook raised concerns regarding international SEO practices. This concern highlights the importance of scrutinizing even expert advice.

The ebook suggested using cross-domain canonical tags for websites with multiple top-level domains (TLDs). This advice is problematic for international SEO. The rel="canonical" tag, typically employed to resolve duplicate content issues, informs Google about the preferred version of similar content pages to index and display. SEO experts often advise against using canonical tags as a blanket solution for duplicate content, particularly in the context of international sites.

Consider a website with three global TLDs: mysite.com, mysite.co.uk, and mysite.de. Following the ebook’s advice would entail setting a canonical link to mysite.com on the .co.uk and .de domains. However, this approach would lead Google to prioritize mysite.com, potentially ignoring the indexing of the .co.uk and .de domains, reducing their visibility in regional Google searches. This misstep could result in a loss of authority for the regional domains.

Use hreflang for Translated Content

The appropriate solution in this scenario is to implement hreflang tags. In its Webmaster Central forum, Google advises against using canonical tags for multiregional websites if the goal is to have them indexed. Instead, Google recommends the rel="alternate" hreflang="x" tag. This tag was introduced explicitly for international (multiregional and multilingual) websites, guiding Google to display the correct regional site version to users.

For example, a website should use hreflang tags as follows:

<link rel="alternate" hreflang="en-us" href=" />
<link rel="alternate" hreflang="en-gb" href=" />
<link rel="alternate" hreflang="de" href=" />

Each regional page’s header should include these tags, considering that hreflang is page-specific. This setup ensures that a Google UK search will display mysite.co.uk, the correct regional version for UK searchers.

While canonical tags are effective for managing duplicate content, they are not suitable for international websites where distinct regional indexing is desired. In such cases, hreflang tags are the recommended approach, as they help Google present the correct regional site version in search results. This distinction and proper implementation are crucial for effective international SEO.


Source: martech.zone