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 VideoObject markup really enough to get your videos indexed in Google?
To help Google find your videos and understand their content, you can provide structured data using schema.org VideoObject markup. This markup can include the title, description, duration, URLs for th...
Danielle Marshak Mar 17, 2021
★★★ Should You Really Use Noindex Rather Than Robots.txt to Deindex a Page?
John Mueller explained on Twitter that when you want to deindex a page that has been previously indexed by the search engine, you need to use the "noindex" meta robots tag and not the robots.txt file....
John Mueller Mar 15, 2021
★★ Does non-textual content really hurt your site's SEO?
Photos, videos, or other files can be problematic in terms of adult content, copyright, malware, or illegal content, and can therefore cause issues in Google Search....
Martin Splitt Mar 10, 2021
★★★ Should you really block JSON files in your robots.txt?
Blocking the crawl of JSON files via robots.txt will prevent the indexing of content that is visible only after rendering on pages that require these JSON files, both on your site and on third-party s...
John Mueller Mar 05, 2021
★★ Should you really regenerate your sitemaps to remove obsolete URLs?
If sitemap files point to non-existent pages or pages with an obsolete URL structure, they need to be regenerated to contain only current URLs. It's a matter of site hygiene rather than crawl budget....
John Mueller Mar 05, 2021
★★ Do JSON requests really impact your crawl budget?
All requests to the server via Googlebot's infrastructure, including JSON files, count towards the crawl budget. However, many JSON requests do not necessarily imply a limitation on crawling regular c...
John Mueller Mar 05, 2021
★★★ How can you compel Google to refresh your JavaScript and CSS files during rendering?
To force Google to update JavaScript and CSS resources during rendering, use a content hash in the URL of the files. This way, Google will identify the new files, unlike persistent cache with identica...
John Mueller Mar 05, 2021
★★★ Why can a 503 code on robots.txt block your site's entire crawl?
Your site is not required to have a robots.txt file, but it must return a successful 200 or 404 response when requested. If Googlebot encounters a connection problem like a 503, it will stop crawling ...
Daniel Waisberg Mar 03, 2021
★★★ What causes a sudden drop in crawl requests that could indicate a robots.txt issue or response time problem?
If you notice a significant drop in the total number of crawl requests, ensure that no one has added a new robots.txt file to your site, or that your site is not responding slowly to Googlebot....
Daniel Waisberg Mar 03, 2021
★★ Does PageSpeed Insights really measure your site's performance?
Lab tests like PageSpeed Insights are predictions of what users might see, not exact measurements. The location of the testing server matters little since connection time plays a minor role compared t...
John Mueller Feb 26, 2021
★★ How does Google truly identify relevant documents for a query?
Google uses posting lists that identify documents containing certain keywords. For example, for a search 'oatmeal cookies', the posting list indicates which documents contain 'oatmeal' and which conta...
Gary Illyes Feb 23, 2021
★★★ Does Google really tokenize all your content or does it discard half of the HTML?
During indexing, Google breaks down documents into tokens and does not retain all of the raw HTML content. Certain HTML elements are kept for specific reasons, as well as the actual words appearing on...
Gary Illyes Feb 23, 2021
★★ Does Google really overlook the scripts and extra content on your pages?
When tokenizing documents, Google does not index all of the unnecessary elements of HTML, such as script text. Only relevant elements and actual words appearing on the page are retained in the index....
Gary Illyes Feb 23, 2021
★★ Can the disavow file actually harm your site?
The disavow file is a technical tool. Google looks at it and if you don’t want those links, Google removes them. It’s not something counted against your site. Google won’t say you must be a spammer be...
John Mueller Feb 19, 2021
★★ Why doesn’t Search Console show all the data from your indexed sitemaps?
In Search Console, you sometimes only see part of the table with sitemap files in a sitemap index. This is more of a reporting issue than an indexing issue. If you were to add the sitemap files indivi...
John Mueller Feb 19, 2021
★★ Should you really rename all your images for SEO?
Google advises in its image search guidelines to use helpful and descriptive file names for images rather than simple numbers. This specifically aids image search....
John Mueller Feb 12, 2021
★★★ Do audio files on your pages really boost your SEO?
Adding an audio version of the content on a page does not help with rankings, except for the obvious improvement in accessibility. Google does not treat audio files as distinct content and does not ra...
John Mueller Feb 12, 2021
★★★ Do you really need a robots.txt file to get indexed by Google?
Having a robots.txt file is totally optional. If no robots.txt file exists, there are no restrictions for robots, and that is a perfectly acceptable setup. The absence of a robots.txt does not affect ...
John Mueller Feb 12, 2021
★★★ Should you really block images in robots.txt to exclude them from Google Images?
If you do not want your page images to be displayed in search, a good way to achieve this is by disallowing their crawling in the robots.txt file. Make sure that the appropriate URLs are correctly blo...
John Mueller Feb 10, 2021
★★★ Could the URL structure of your images be sabotaging your SEO?
Google uses the URL path as well as the filename to help understand your images. Organize the content of your images so that the URLs are constructed logically. Avoid changing your image URLs....
John Mueller Feb 10, 2021
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