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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★★ Why does Google only communicate about a fraction of its algorithm updates?
Google made over 4,000 updates in 2021. Many of these changes are minor and are not announced. The most important ones, particularly those on which site owners can act, are announced and listed in the...
John Mueller Sep 07, 2022
★★★ Should You Follow the Quality Raters Guide to Improve Your SEO Rankings?
John Mueller indicated on Twitter that the Quality Raters guidelines document was not a list of tips for ranking better on Google. However, reading it could provide insights into content quality and h...
John Mueller Aug 29, 2022
★★ Should you block your decorative JavaScript files to optimize your crawl budget?
If JavaScript files are purely decorative and add neither content nor value to the page rendering, they can be blocked via robots.txt or X-Robots-Tag. Rendering will fail for these resources but this ...
Gary Illyes Aug 25, 2022
★★ Are you wasting your crawl budget on JavaScript files that add no value?
If a significant proportion of crawl budget (35% or 90%) is consumed by JavaScript files that add no content, it is recommended to consolidate these files or use X-Robots-Tag headers to prevent their ...
Gary Illyes Aug 25, 2022
★★★ Should you really multiply structured data on your pages to please Google?
Google never penalizes you for having more precise structured data on your pages. However, it is more effective to focus on the types that Google actively uses, documented in Google's Search Gallery....
Ryan Levering Aug 23, 2022
★★★ Should You Abandon Dynamic Rendering for SEO in 2024?
Google has updated its documentation for JavaScript developers and now indicates that Dynamic Rendering is "a workaround and not a long-term solution for JavaScript-generated content issues in search ...
Google Aug 16, 2022
★★★ How Do You Count the 50,000 URL Limit in XML Sitemaps Without Making Mistakes?
John Mueller explained on Twitter that the 50,000 URL limit in XML Sitemaps applies only to the number of URLs submitted through the "loc" tag. If there are other URLs in the file, such as with the "a...
John Mueller Aug 16, 2022
★★★ Can an iframe with noindex block the indexing of the main page?
John Mueller explained on Twitter that if a parent page containing a meta robots "index" tag displayed an HTML file (child) containing a meta robots "noindex" tag in an iframe, the parent page would b...
John Mueller Aug 08, 2022
★★★ Why is Google now rejecting certain directives in your robots.txt file?
The robots.txt file should only be used to control crawling. Google removed certain directives like noindex from the robots.txt parser because they don't concern crawling. Indexing and serving must be...
Gary Illyes Aug 04, 2022
★★★ Should you use X-Robots-Tag to keep PDFs and binary files out of Google's index?
For binary files like PDFs where it's impossible to add a meta tag, Google supports the X-Robots-Tag HTTP header with noindex. This header works like a meta noindex and will be processed during indexa...
Gary Illyes Aug 04, 2022
★★★ Do Noindex Pages Really Impact Your Core Web Vitals?
In an official document, Google states that a page marked as "noindex" cannot impact the overall Core Web Vitals score of the site to which it belongs....
Google Aug 01, 2022
★★★ How does Googlebot's 15 MB limit affect your SEO strategy?
The 15 MB limit for Googlebot applies to the uncompressed file (after extraction), not the compressed one. If an uncompressed HTML file exceeds 15 MB, it is highly recommended to reduce it (externaliz...
Kanatani Takeaki Jul 28, 2022
★★ How does the 15 MB limit impact your JavaScript management for SEO?
The 15 MB limit applies only to the initially retrieved HTML file, prior to the execution of JavaScript. Content generated by JavaScript through onload events or Ajax is not included in this initial l...
Google Jul 28, 2022
★★★ Is it true that Googlebot only crawls the first 15 MB of HTML files?
Googlebot fetches and processes only the first 15 MB of a file during the initial request. This limit applies to the source HTML file before executing JavaScript, CSS, or other resources. Most sites a...
Google Jul 28, 2022
★★ How does support for the M3U8/HLS format influence your video SEO?
The M3U8 (HLS) format is supported by Google for videos, even though it is not explicitly mentioned in the official documentation. If you face any implementation issues, it is recommended to contact t...
Ogawa Anna Jul 28, 2022
★★★ Why is the 15 MB limit on uncompressed files crucial for SEO?
The 15 MB limit from Googlebot applies to the file after decompression, not to the size of the compressed file. If an HTML file exceeds this limit, even after compression, it's recommended to reduce i...
Google Jul 28, 2022
★★★ Why is the 15 MB limit before JavaScript execution crucial for your SEO?
The 15 MB limit concerns the initial HTML file retrieved, before JavaScript execution. The dynamically generated content by JavaScript (onload, AJAX) after the initial load is not counted within this ...
Kanatani Takeaki Jul 28, 2022
★★★ How does Googlebot's 15 MB limit influence your SEO strategy?
Googlebot recognizes only the first 15 MB of the initial retrieved HTML file. This limit applies to the source file before JavaScript, CSS, or other resources are executed. It does not pertain to reso...
Kanatani Takeaki Jul 28, 2022
★★ Is it true that Google supports the M3U8/HLS format for videos?
Google supports M3U8 and HLS video formats even though they are not explicitly mentioned in the official documentation. If you experience any implementation issues, it is advisable to report the case....
Google Jul 28, 2022
★★★ Should you really follow Google's guidelines to the letter for SEO?
To improve a site's visibility in Google Search, it is recommended to follow Google's Webmaster guidelines, read the SEO beginner's guide, and visit the Webmaster portal where all the necessary docume...
Google Jul 20, 2022
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