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 still use the Disavow Tool to manage spam links?
Google generally manages spam links well automatically without the need for intervention. However, if a webmaster detects a massive influx of spam links (for instance, hundreds of spammy domains), the...
John Mueller Jun 26, 2020
★★★ Why does Google crawl your JS/CSS files but never indexes them?
Crawling involves making an HTTP request and retrieving the result. Rendering executes the crawled JavaScript in a browser to produce the content. Indexing stores useful content to display to users. J...
Martin Splitt Jun 23, 2020
★★★ Does unsupported structured data really affect ranking?
Building a network of structured data between pages with types unsupported by Google has no visible effect on ranking. Google primarily uses the types documented in its developer guide. The rest is ei...
John Mueller Jun 23, 2020
★★★ Should you unblock JavaScript and CSS in robots.txt for better SEO?
Blocking access to JavaScript and CSS files via robots.txt prevents Google from downloading these resources, which can cause rendering issues. If content is generated by JavaScript or if non-native la...
Martin Splitt Jun 23, 2020
★★ Do you really need to stick to the supported page types for the reviewed-by schema?
The reviewed-by markup can only be used on officially supported page types (e.g., Medical Page). If schema.org does not allow it to be added to NewsArticle, you should not force a non-compliant implem...
John Mueller Jun 23, 2020
★★ Is it really necessary to avoid duplicate meta tags in HTML and JavaScript?
Having duplicate meta tags (for example, in index.html and via React Helmet) is problematic. You need to either remove them from the static HTML file and generate them solely through the JavaScript fr...
Martin Splitt Jun 23, 2020
★★★ Do you really need to fix ALL pages to lift a Google manual action?
To resolve a manual action, you need to fix the issue on ALL affected pages. Fixing only some pages will not resolve the issue. A good reconsideration request must explain the exact problem, detail th...
Daniel Waisberg Jun 18, 2020
★★ Does FOUC really harm your organic SEO?
Flash of Unstyled Content happens because the browser can paint the content before the CSS loads by using its default stylesheet (system fonts, black headings, blue underlined links). Inlining the cri...
Martin Splitt Jun 17, 2020
★★★ Does Googlebot really download images during the main crawl?
For the main web crawl, Google generally does not download the image files themselves, only the URLs of the images, their alt text, and their context. This is why images can fail to load in testing to...
Martin Splitt Jun 17, 2020
★★ Where can you find Google's official JavaScript SEO documentation?
Google maintains up-to-date and comprehensive documentation on JavaScript SEO in the Guides section of developers.google.com/search, including specific JavaScript SEO guides regularly updated by Marti...
Martin Splitt Jun 17, 2020
★★ Does FOUC really ruin your Core Web Vitals performance?
FOUC (Flash of Unstyled Content) occurs because the browser can render content before downloading the CSS, using its default stylesheet. To prevent this, critical styles should be inlined directly in ...
Martin Splitt Jun 17, 2020
★★ Should you add a noindex to JavaScript and CSS files?
Adding a noindex header to JavaScript or CSS files is generally not useful because these files are typically not indexed. This is not an issue, but not blocking these resources via robots.txt is more ...
Martin Splitt Jun 17, 2020
★★★ Should you really ignore noindex settings for your JS and CSS files?
Adding a noindex directive in the HTTP headers of JavaScript or CSS files is generally unnecessary as they are not usually indexed. However, you must not block their crawl via robots.txt, as this can ...
Martin Splitt Jun 17, 2020
★★★ Should you really limit the number of HTTP resources per page for SEO?
Google does not impose a strict limit on the number of HTTP resources per page. Fewer resources are generally better to reduce the risks of loading failures, but you must be reasonable: putting everyt...
Martin Splitt Jun 11, 2020
★★ Should You Ditch Search Console's URL Parameters Tool in Favor of Robots.txt?
John Mueller explained on Twitter that the URL parameters handling tool in Search Console does not replace a "clean" use of robots.txt to block crawling on complex URLs with parameters, and that robot...
John Mueller Jun 08, 2020
★★ Are Search Console tools really enough to solve your indexing problems?
To resolve indexing issues, check the registration in Search Console, submit an indexing request via the URL Inspection Tool, and send an XML sitemap. If the problem persists, provide detailed screens...
金谷武明 Jun 04, 2020
★★ Should you really submit all paginated pages in the XML sitemap?
For a large site with pagination, it is not necessary to send all pagination pages (page 2, 3, 100…) in the XML sitemap. Google recommends only submitting important pages. Since the rel=next/prev attr...
Anonyme (金谷武明) Jun 04, 2020
★★ Does the number of JavaScript files really slow down Google indexing?
Google renders all JavaScript files on a page in a single rendering pass, not file by file. The number of JS files does not proportionally increase the rendering delay in the indexing process....
金谷武明 Jun 04, 2020
★★ Does the rel=canonical via HTTP header really still work?
The rel=canonical attribute via HTTP header continues to work and remains effective for PDFs or other content with separate desktop/mobile versions on different domains....
金谷武明 Jun 04, 2020
★★ Does the HTTP header rel=canonical really work to manage duplicate content?
The rel=canonical attribute specified via the HTTP header is still recognized and effective. Google recommends using it if pages (like PDFs) are duplicated across multiple domains (separate PC and mob...
Anonyme (金谷武明) Jun 04, 2020
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