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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★★★ Should you really make your JavaScript files accessible to Googlebot?
JavaScript files that are important for loading content on a page must be accessible to Google; they should not be blocked in the robots.txt if this prevents Google from accessing relevant content....
John Mueller Aug 24, 2017
★★ Should you really clean your Disavow file of dead and redirected URLs?
Redirected domains or those with HTTP errors like 404 or 500 can remain in the Disavow file, but it is not necessary to actively maintain defunct URLs in this file....
John Mueller Aug 24, 2017
★★ Should you really keep your Disavow file even with dead domains?
Disavowed links in disavow files are ignored by Google and do not affect SEO rankings. Therefore, you do not have to delete these files even if the linked domains show errors or are no longer online....
John Mueller Aug 24, 2017
★★★ Does the Disavow file really nullify all disavowed backlinks?
Links disavowed via the Disavow file will not be used for your site by Google, even if these backlinks are not intrinsically harmful according to Google....
John Mueller Aug 24, 2017
★★★ Should you really use the disavow file in SEO?
Google advises using the disavow file only when you identify undesirable and artificial links that could harm your site....
Google Aug 23, 2017
★★★ Can Google really discover and index all the JavaScript links on your site?
Google can discover URLs even if they are generated by JavaScript, as URLs present in JavaScript files can be crawled and indexed....
Google Aug 23, 2017
★★ Can you really declare multi-domain sitemaps via robots.txt, or should you go through Search Console?
To include sitemaps from multiple domains, you can either include the sitemap directive in the robots.txt file of each domain or use a site management tool like Google Search Console to prove ownershi...
Google Aug 23, 2017
★★ What are the only two fields in an XML sitemap that Google actually cares about?
John Mueller explained on Twitter that in XML files, the two most important fields are the URL (<loc>) and the last modification date (<lastmod>)....
John Mueller Aug 21, 2017
★★★ Why Is Google Indexing More URLs Than Those Declared in Your XML Sitemap?
A user pointed out to John Mueller that in their Search Console, the XML Sitemaps report indicated there were more indexed URLs than URLs in the Sitemap. John responded that this likely came from the ...
John Mueller Aug 21, 2017
★★★ Does CSS File Size Really Impact Your SEO Rankings?
John Mueller indicated on Twitter that the size of a stylesheet (CSS) file does not impact the search engine's algorithm. It can be several tens of MB....
John Mueller Aug 14, 2017
★ Does disavowing poor-quality backlinks really carry a negative impact?
Gary Illyes indicated on Twitter that a disavowed site, therefore designated as providing low-quality links, was not negatively impacted subsequently by Google's algorithm. The links it provides are s...
Gary Illyes Aug 14, 2017
★★ What's the Maximum Page Size Google Will Actually Crawl?
John Mueller explained that Googlebot's current crawl limit for a web page is 200 MB (the last known limit in 2015 was 10 MB)....
John Mueller Aug 14, 2017
★★★ Should you really disavow low-quality links if faced with a negative SEO attack?
In the case of negative SEO attacks with low-quality links, use a disavow file to instruct Google to disregard these links....
John Mueller Aug 11, 2017
★★★ Should you really count words to rank on Google?
Google does not recommend counting the maximum number of words on a page. The file size could technically limit indexing, but it does not significantly affect a page unless a script produces an infini...
John Mueller Aug 10, 2017
★★★ Does the Order of URLs in an XML Sitemap File Actually Matter to Google?
John Mueller explained on Twitter that you can structure your XML Sitemap file absolutely however you want in terms of field order, and this won't cause any problems for Google. The file is read autom...
John Mueller Aug 07, 2017
★★★ Is Google's SEO Guide from 2010 Still Relevant Today?
Gary Illyes indicated on Twitter that the SEO starter guide published and offered (in PDF format) by Google was still current and relevant, even though it hasn't been updated since 2010 (as clearly sh...
Gary Illyes Aug 07, 2017
★★★ Does Google Really Consider a Disavow File as a Spam Signal?
In the series of odd questions, another internet user asked Gary Illyes whether submitting a disavow file to Google for a site was a spam signal for the search engine. Gary naturally replied that it w...
Gary Illyes Aug 07, 2017
★★★ How does Google really choose which canonical URL to index?
Google uses several signals to determine which URL is canonical, including redirects, meta rel=canonical tags, internal links, XML sitemaps, and external links. It is important that this information i...
John Mueller Jun 30, 2017
★★★ Why does Google overlook robots.txt files located in subdirectories?
Google only reads the robots.txt file from the root directory of a domain or subdomain. Robots files in subdirectories are not considered....
John Mueller Jun 29, 2017
★★★ What happens if your robots.txt file is blocked or inaccessible?
Blocking a robots.txt file makes Google unable to crawl other pages on the site. It is essential that the file returns a 404 response if it does not exist or valid content to allow crawling....
John Mueller Jun 26, 2017
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