What does Google say about SEO? /
This category compiles all official Google statements regarding the processing and indexing of non-HTML file formats, including PDF documents, Flash files (SWF), and XML documents. Optimizing these file types represents a critical challenge for SEO professionals managing websites with extensive technical documentation, reports, catalogs, or structured content. Google's ability to crawl and index these resources has evolved significantly over the years, making it essential to understand their official recommendations. PDF files receive special treatment in search results, with specific implications for optimization, markup, and accessibility. Legacy technologies like Flash have been progressively deprecated, while structured formats such as XML play a vital role in search engine communication through sitemaps. This section aggregates Google's official positions on optimization best practices, technical limitations, recommended alternatives, and indexing strategies for each file type. Whether you're dealing with document repositories, legacy content migration, or structured data implementation, these official declarations provide authoritative guidance for handling alternative content formats. An invaluable resource for any SEO practitioner facing the challenges of optimizing and ranking non-HTML content in Google search results.
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★★ Is your website still using plugins to display content? Here's why Google says you need to stop immediately
Browser plugins such as Flash should not be used to display content. With the evolution of the web and JavaScript APIs, plugins have become obsolete and are no longer supported....
Gary Illyes Feb 03, 2022
★★★ Do you really need to update ALL internal elements after a URL migration?
You must update all internal elements of the site: links, forms, structured data, sitemaps and robots.txt file so they point to the new URLs....
John Mueller Jan 18, 2022
★★ Should you really document every single URL during an SEO migration?
It is essential to create a list documenting all old URLs and their new correspondences. This list allows you to track and verify changes after the migration....
John Mueller Jan 18, 2022
★★★ Should you really use the Disavow tool only for purchased links?
The Disavow file should only be used for links where it is 100% obvious they were purchased or exchanged. Random links from spam sites, forums, or copied pages do not need to be added to the Disavow f...
John Mueller Jan 14, 2022
★★ Does a bloated robots.txt file really hurt your SEO rankings?
A very large robots.txt file (over 1500 lines) has no direct negative SEO impact. However, it makes maintenance more difficult and increases the risk of accidental errors that could cause problems....
John Mueller Jan 14, 2022
★★ Does the domain directive in your Disavow file really help you bypass Google's 2MB limit?
The Disavow file limit is 2MB. To optimize space, it is recommended to use the domain directive as much as possible rather than listing each URL individually....
John Mueller Jan 14, 2022
★★ Should you test removing your Disavow file incrementally, or can you delete it all at once?
To test the removal of a Disavow file, it is recommended to proceed incrementally by dividing the file into parts and gradually removing sections to assess the impact, rather than deleting everything ...
John Mueller Jan 14, 2022
★★★ Does it really matter whether you submit your sitemap in robots.txt or Search Console?
All different sitemap submission methods are equivalent for Google. Including the sitemap in the robots.txt file provides no particular SEO advantage compared to submission via Search Console....
John Mueller Jan 14, 2022
★★★ Can we really trust Google's official documentation?
Google's official documentation is not always immediately synchronized with internal technical developments. The team does its best to keep the documentation up to date, but discrepancies can occasion...
Martin Splitt Jan 13, 2022
★★ Does Google really pay attention to your feedback on its SEO documentation?
Comments left directly on Google’s documentation pages are read by the team, even if no direct response is visible. These comments are used for continuous improvement of the documentation....
Martin Splitt Jan 13, 2022
★★ Is it true that Lighthouse scores are calculated transparently?
The Lighthouse team provides comprehensive documentation explaining how scores are calculated and how the weighting of different metrics evolves over time, allowing for total transparency in evaluatio...
Martin Splitt Jan 13, 2022
★★★ What's Google's HTML Code Size Limit for Indexing?
John Mueller reminded us, also on Twitter, that the size of a web page's source code indexed by Google had a limit in terms of weight, but that it was very high: "We don't have a documented limit, the...
John Mueller Jan 03, 2022
★★ Should you really rely solely on Google's official documentation?
To avoid misunderstandings between developers and SEO professionals, it is essential to always refer to the official documentation rather than conspiracy theories or urban legends in the SEO industry....
Martin Splitt Dec 29, 2021
★★★ Why does Google need a dedicated SEO team for its own site?
Google's SEO team works on the Search Central site by improving content, titles, descriptions, and internal linking to enhance page discoverability. This team is isolated from the research teams and r...
John Mueller Dec 23, 2021
★★★ Should you really react quickly after a Google algorithm update?
Google's algorithm updates primarily concern long-term changes in search and are generally not influenced by rapid adjustments of websites. It is advisable to take a step back, read the documentation,...
John Mueller Dec 23, 2021
★★★ Is it true that Google really prioritizes high-quality product reviews?
The December 2021 product review update aims to better promote high-quality product reviews. Google provides documented best practices on what constitutes a quality product review....
John Mueller Dec 23, 2021
★★★ Does the robots.txt file really prevent the indexing of your pages?
The robots.txt file is used to control crawling by automated bots. Google can index URLs blocked by robots.txt without retrieving their content, based solely on external links pointing to those pages....
Gary Illyes Dec 21, 2021
★★ Is resubmitting your XML sitemap really a waste of time?
Resubmitting an XML sitemap without real changes is not a strong signal for Google. If you manually modify all the dates to force a recrawl, Google will detect that all the dates are identical and wil...
John Mueller Dec 18, 2021
★★ How do web fonts disrupt SEO with Cumulative Layout Shift?
External font files can lead to CLS issues if content initially displays without the font and then rearranges once the font is loaded. Chrome DevTools allows you to block the font URL to test if it is...
John Mueller Dec 18, 2021
★★ Should you really convert your images from JPEG to WebP for better SEO?
Changing image URLs (for example, from JPEG to WebP) can affect rankings in Google Images, as it takes time for the changes to be reflected. Some users employ the same file extension to serve WebP, wh...
John Mueller Nov 26, 2021
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