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 abandon complete unbundling of your JavaScript files?
Fully unbundling JavaScript bundles into multiple separate files is not recommended because browsers have a limit on simultaneous HTTP connections per host, which slows down loading. Route-based code ...
Martin Splitt May 05, 2020
★★★ Is it really necessary to split your sitemap into multiple files to index a large site?
If you have a large number of URLs to index, it is acceptable to divide your sitemap into multiple sub-sitemaps as long as you adhere to Google's limit of 50,000 URLs per sitemap file....
Martin Splitt Apr 29, 2020
★★★ Can Googlebot really execute your AJAX requests and index the JavaScript-loaded content?
Googlebot can execute AJAX requests when rendering a page, particularly to load additional content displayed with JavaScript. Therefore, it is crucial not to block these requests in the robots.txt fil...
John Mueller Apr 28, 2020
★★★ Should you really clean up all internal links after a 301 redirect?
To help Google focus on the new URL after a 301 redirect, it is advisable to update internal links, sitemap files, and any other references pointing to the original page so that they point to the new ...
John Mueller Apr 22, 2020
★★★ Do lastmod tags in sitemaps really affect crawling?
Including last modification dates in sitemap files is recommended, as it helps prioritize pages for crawling. The absence of these tags for certain URLs has no negative effect....
John Mueller Apr 09, 2020
★★★ Why isn't a 301 redirect enough to remove content from Google's index?
A 301 redirect is not enough to remove content from Google’s search results. Similarly, a directive in the robots.txt file will not block indexing....
Daniel Waisberg Apr 07, 2020
★★★ Should You Worry About External Resources (JS/CSS) Blocking for SEO?
Martin Splitt indicated during a hangout that it generally does not pose major SEO problems if external resources (JavaScript or CSS files) that are hosted elsewhere than on the site using them are bl...
Martin Splitt Apr 06, 2020
★★★ Does the disavow file really work link by link as Google crawls?
The disavow file works incrementally on an individual link basis, and links will be ignored as they are crawled....
John Mueller Apr 03, 2020
★★★ What really happens when Googlebot can't access your robots.txt?
The robots.txt file allows webmasters to specify access to their site. Before crawling any URL, Googlebot always checks the robots.txt file. If the robots.txt file is not accessible or returns a persi...
Jin Liang Apr 02, 2020
★★★ Do descriptive titles and file names really impact image SEO?
Google encourages the use of descriptive titles and captions as well as explicit file names for images, as this information is used to provide context for images and help answer user queries by indica...
Francois Spies Apr 01, 2020
★★ Why do PDFs slow down a site migration?
Google may take longer to process PDF files during a site migration, especially if they are large. This is because PDFs are updated less often and, therefore, crawled less frequently....
John Mueller Mar 26, 2020
★★★ Should you still disavow backlinks in SEO?
Google is attempting to filter out irrelevant links and suggests using a disavow file only if you suspect link manipulation that could be harmful....
John Mueller Mar 26, 2020
★★★ Do third-party fonts really hinder your SEO?
Third-party fonts can slow down websites. It is suggested to cache them locally or use the CSS 'font-display' property for asynchronous loading. Another solution is to reduce the weight of font files ...
Martin Splitt Mar 26, 2020
★★★ Why does Google crawl PDFs so infrequently, and how can you manage their migration?
Google does not frequently crawl PDF files because they rarely change. During a domain migration, if there are clear redirects, Google can process this quickly, but if there are too many variations, i...
John Mueller Mar 26, 2020
★★★ Is blocking JS and CSS in robots.txt an SEO mistake or a legitimate strategy?
Blocking JavaScript or CSS with robots.txt is not cloaking, but it can be problematic if the content relies on these blocked files to appear. Google cannot index content that is not visible in the ren...
Martin Splitt Mar 26, 2020
★★ Do you really need to ping Google after every sitemap update?
The structure of sitemaps should be optimized to include recently modified URLs. It is beneficial to ping Google after updating a sitemap to ensure that these changes are recognized....
John Mueller Mar 20, 2020
★★★ Should You Really Block Internal Search Results Pages from Indexing?
John Mueller explained on Twitter that it was important not to index internal search engine results pages. Not for spam reasons, but because it can generate an infinite number of pages and drown quali...
John Mueller Mar 16, 2020
★★★ Do You Really Need an XML Sitemap to Improve Your SEO Rankings?
In a video on the YouTube channel for webmasters dedicated to XML Sitemaps, Googler Daniel Waisberg explains that these files are primarily interesting in 3 or 4 cases: if the site is very large, if c...
Google Mar 09, 2020
★★★ How can you permanently delete a URL from Google's index without leaving a trace?
For Google to stop indexing a URL, it must return a 404 code or be blocked via a robots.txt file. For complete removal from the index, use the noindex directive or require HTTP authentication....
Google Mar 04, 2020
★★ Do you really need to split your sitemaps into multiple files?
Sitemap files have limits regarding the number of URLs and maximum size. If necessary, you can create multiple sitemap files and submit them together with an index file....
Google Mar 04, 2020
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