What does Google say about SEO? /
The Crawl & Indexing category compiles all official Google statements regarding how Googlebot discovers, crawls, and indexes web pages. These fundamental processes determine which pages from your website will be included in Google's index and potentially appear in search results. This section addresses critical technical mechanisms: crawl budget management to optimize allocated resources, strategic implementation of robots.txt files to control content access, noindex directives for page exclusion, XML sitemap configuration to enhance discoverability, along with JavaScript rendering challenges and canonical URL implementation. Google's official positions on these topics are essential for SEO professionals as they help avoid technical blocking issues, accelerate new content indexation, and prevent unintentional deindexing. Understanding Google's crawling and indexing processes forms the foundation of any effective search engine optimization strategy, directly impacting organic visibility and SERP performance. Whether troubleshooting indexation problems, optimizing crawl efficiency for large websites, or ensuring proper URL canonicalization, these official guidelines provide authoritative answers to complex technical SEO questions that shape modern web presence and discoverability.
Quick SEO Quiz

Test your SEO knowledge in 5 questions

Less than a minute. Find out how much you really know about Google search.

🕒 ~1 min 🎯 5 questions
★★ Do uppercase URLs really create duplicate content that Google penalizes?
Google treats URLs as case-sensitive. Identical URLs with uppercase/lowercase variations create technical duplicate content. Small sites manage this easily, but very large sites must normalize via con...
John Mueller Sep 04, 2020
★★★ Is the URL switch between AMP and canonical HTML capable of really harming your ranking?
Switching from the AMP version to the canonical HTML version (or vice versa) does not change the page ranking. It’s solely a matter of displayed URL. If a drop in ranking coincides with an AMP change,...
John Mueller Sep 04, 2020
★★★ Should you really worry when a 404 page turns back to 200?
Changing a 404 page to 200 does not incur any penalty. Google normally reindexes the new content. However, a long-term 404 page gets crawled less frequently (possibly every two months). Thus, repeated...
John Mueller Sep 04, 2020
★★ 404 or noindex for deindexing: which method should you really prefer?
Using 404 or noindex to remove pages from the index produces the same final result. Noindex can be slightly faster, but the difference is negligible at the scale of a site. Choose the most practical m...
John Mueller Sep 04, 2020
★★★ Are structured data really unnecessary for Google SEO?
Structured data is not a requirement for a page to be indexed or ranked by Google. If a single page on a site lacks structured data or a specific type like mainEntity, it won't be an issue for SEO....
John Mueller Sep 04, 2020
★★★ Hreflang in HTML or XML Sitemap: Is There Really a Difference for Google?
For implementing hreflang, Google treats the <head> HTML tag and the declaration in an XML sitemap exactly the same. Both methods are equivalent, and the choice depends on the ease of implementation f...
John Mueller Sep 04, 2020
★★★ Homepage with URL Parameters: Should You Really Index Multiple Versions or Canonicalize Everything?
A homepage with parameters and one without are two distinct URLs for Google. If the versions are indeed different (personalized content), they can be indexed separately. If they are equivalent, use re...
John Mueller Sep 04, 2020
★★★ Is server authentication the only real shield against indexing staging environments?
The best method to prevent the indexing of staging environments is server-side authentication (password or IP restriction). While robots.txt or noindex tags work, they can be mistakenly pushed to prod...
John Mueller Sep 04, 2020
★★ Can your staging URLs be indexed even without any links pointing to them?
Even without visible links, development URLs can be discovered by Google through browser extensions that track website popularity or through public mailing lists where developers share links via email...
John Mueller Sep 04, 2020
★★★ Should You Include Category Pages in Your XML Sitemap?
In response to a tweet asking whether category page URLs - article or product listing pages - should be included in the XML Sitemap, Fabrice Canel (Bing) answered yes, this file should include all URL...
Google Aug 31, 2020
★★ Should you really leave the robots.txt file unchanged during an SEO migration?
Do not change the configuration of the robots.txt file during a migration. If certain URLs were blocked by robots.txt for good reasons before the migration, they must remain blocked after the migratio...
Martin Splitt Aug 27, 2020
★★★ Should you really use Google Search Console's address change tool during a migration?
The address change tool in Search Console explicitly tells Google that a migration is intentional and not temporary or accidental. This additional signal allows Google to reprioritize the crawl, make ...
Martin Splitt Aug 27, 2020
★★★ How does Google really transfer signals during a domain migration?
When Google crawls the old site and detects the redirects, it checks that the new site is a one-to-one copy of the old one. If that's the case, signals from the old domain are transferred to the new d...
Martin Splitt Aug 27, 2020
★★★ Should you really redirect all images during a site migration?
It is essential to implement 301 redirects for all images during a site migration. Visual content is very important for SEO. Since refreshing in the image index takes time, you should monitor the serv...
Martin Splitt Aug 27, 2020
★★★ Merging two websites: Why doesn’t Google treat this like a standard migration?
Merging two websites into one is not a standard site migration. It involves creating a new site that combines two existing versions, which requires Google to re-crawl numerous pages. The outcome and p...
Martin Splitt Aug 27, 2020
★★ How long does it really take to transfer SEO signals during a migration?
The speed of signal transfer depends on the site's crawl budget, crawl frequency, and the number of external links. This can take anywhere from one day to several weeks depending on these factors. Sit...
Martin Splitt Aug 27, 2020
★★★ Should you really roll back after a site migration fails?
Before contemplating a rollback, it’s essential to diagnose the cause of the issue (missing redirects, crawl problems, technical errors). If after a month no improvement is observed, no explanation is...
Martin Splitt Aug 27, 2020
★★★ How Does Google Actually Determine the Canonical URL of Your Pages?
John Mueller provided on Twitter a list of criteria that Google takes into account to define what the canonical URL of a page is (and therefore its "canonicalization"): redirects, internal links, exte...
John Mueller Aug 24, 2020
★★★ Should You Index Automatically Translated Content Without Human Review?
Gary Illyes indicated on Twitter that the official recommendation was not to index content that would be translated automatically (with software/algorithm like GPT-3) without subsequent human review. ...
Gary Illyes Aug 24, 2020
★★★ Does the Mobile First Index Really Apply Automatically to New Websites?
Google indicated in May 2019 that starting from July 1st of that same year, all new sites discovered by the search engine's crawlers would automatically be integrated into the Mobile First Index. John...
John Mueller Aug 24, 2020
🔔

Get real-time analysis of the latest Google SEO declarations

Be the first to know every time a new official Google statement drops — with full expert analysis.

No spam. Unsubscribe in one click.