After Webcertain improved the client’s hreflang, Google started considering hreflang for this website (previously, it had ignored it as it had contained too many errors).

The website’s organic click-through rate increased consistently from the moment the hreflang started to be considered, showing the strategy was working.

It looks like the hreflang is starting to help Website 1 rank over Website 2 for some of the part numbers that are relevant. If only they had implemented this 3-4 years ago, when your team first suggested it!

Anonymous, SEO Program Manager, Manufacturing Client.


The client wanted Google to serve a specific US website (only available in the US) when needed, over the international website and/or the local equivalents for certain product ranges, as appropriate.

To do this, the client needed help to improve the XML sitemap with hreflang deployment for two of its main websites.


We created an application to process and analyse the sitemaps and tested it.

We analysed the hreflang construct, identifying all errors that were present.

We conducted a crawl to check if the URLs within the sitemap were valid or not.

We worked alongside the client’s IT team, recommending the best ways to implement the necessary fixes.


  1. We imported all XML sitemaps into a single large array as they needed to be processed together. The result was an array with 3.6 million declared URLs and around 42 million hreflang links.
  2. The matrix was checked for XML integrity, meaning correct hreflang self-references, complete bi-directional referencing, and unlinked hreflang.
  3. We analysed the URL validity (non-200 URLs, non-200 hreflang, non-indexable URLs/hreflang) through full crawls.
  4. We accommodated data processors to work in segments (e.g. by locale) to find patterns quicker.
  5. We produced final documentation, highlighting all the errors and providing clear recommendations to be considered.
  6. We organised ongoing calls with the client’s IT team, answering questions and advising on the best procedures to implement the fixes.

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