Canonical Domain

The canonical domain is the version of the domain which has been set as the preferred version for indexing. This helps to combat the issues of duplicate content and inform search engines of the domain you would like to be indexed. Our Hangout Notes cover examples and recommendations from Google for correctly setting and handling canonical domains.

Fine to Add Canonical From Secondary Domains to Preferred Domain

August 25, 2017 Source

John says it’s fine to use a different domain or set of URLs for offline marketing and to implement a canonical pointing to your preferred domain.


Content in Iframes May be Indexed on the Embedding Page

June 30, 2017 Source

Pages embedded within an iframe on another page may be indexed as content on the embedding page as it will be seen when the page is rendered. You can use X-Frame-Options to prevent browsers from embedding a page which Google will respect.


Mobile URLs Won’t Need to be Included in Sitemaps for Mobile-first Indexing

May 30, 2017 Source

It won’t be necessary to include mobile pages in sitemaps for Mobile-first indexing. You should continue to include on your canonical desktop pages. Google’s goal is to keep everything as similar as possible while indexing content on mobile pages.


Google Automatically Chooses a Preferred Domain Based on Multiple Signals

March 10, 2017 Source

Google uses many factors to determine the canonical domain including redirects, canonicals, internal links, sitemaps and backlinks, so choosing a preferred domain in Search Console is not critical.


Google Chooses HTTP if the HTTPS contains Insecure Content

December 16, 2016 Source

If Google finds insecure content on the HTTPS version of a URL, it is more likely to choose HTTP as the canonical version.


Backlinks are reported in Search Console on the canonical domains

December 16, 2016 Source

If you canonicalise domain variants (www/non-www/http/https), all of the backlinks will be reported in Search Console under the canonical domain.


Separate Non-WWW/WWW and HTTP>HTTPS Redirects are OK

October 4, 2016 Source

It’s OK to use separate redirects for Non-WWW to WWW and HTTP to HTTPS which can result in 2 steps. Ideally you would redirect in a single step where possible.


Prevent Test Site Being Indexed with Canonical

July 29, 2016 Source

John recommends using a canonical to the main site, although he says that it’s possible for both to be indexed.


Mobile Sites Don’t Need Sitemaps

May 17, 2016 Source

Separate mobile sites should be canonicalising to the desktop page, so you don’t need to submit them to Google via a Sitemap, but it’s still worth adding to Search Console.


Related Topics

HTTPS Parameters Site Architecture URL Architecture Subdomains Facets TLDs Site/Page Quality