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 convert your SVGs into pixel images internally?
Google converts SVG files into pixel images internally to process them consistently with other images, particularly to create thumbnails and manage sizing. Vector formats like SVG do not have a well-d...
John Mueller Feb 05, 2021
★★ How does Google determine the order of images on a single page?
Google uses several factors to rank images: page titles, file names, captions, alt text, and image quality. For several images on the same page, Google may display them in a different order based on p...
John Mueller Feb 05, 2021
★★ Does Google prioritize image quality over the display order on the page?
Google uses several factors to determine which image to display from a page: titles, filenames, captions, alt text, and also the quality of the image. The systems may sometimes prefer a higher quality...
John Mueller Feb 05, 2021
★★ Why does Google convert your SVGs to PNGs and how does it affect your image SEO?
Google converts SVG files into pixel images (PNG) for internal processing and thumbnail display in Image Search. This allows SVGs to be treated like other image formats and to create thumbnails at the...
John Mueller Feb 05, 2021
★★ Does using HTTPS for your XML sitemap namespace hurt your SEO ranking?
In XML sitemaps, the namespace can be declared in HTTP or HTTPS without functional impact. Google treats both the same way. However, for consistency and maintenance reasons, it is recommended to follo...
Google Jan 28, 2021
★★ Does the http:// or https:// namespace in an XML sitemap really affect crawlability?
In the XML Sitemap, using http:// or https:// for the namespace URL (xmlns) has no functional importance. Google treats both identically. Conventionally, http:// is more common....
Google Jan 28, 2021
★★ Does JavaScript really affect your crawl budget?
JavaScript can impact the crawl budget if the site contains many JavaScript files to fetch or if the JavaScript makes numerous API requests. However, for websites with fewer than one million pages, th...
Martin Splitt Jan 27, 2021
★★★ Is it really time to stop manually submitting your pages to Google?
For most sites, there shouldn't be a need to use manual submission systems. They should instead focus on good internal linking and proper sitemap files. If a site does these things well, Google's syst...
John Mueller Jan 27, 2021
★★ Can a XML sitemap really trigger a targeted recrawl of your pages?
To increase a site’s crawl rate, one can update the XML sitemap file to indicate that pages have changed, which may encourage Google to recrawl them. You can also request indexing for priority pages, ...
Martin Splitt Jan 27, 2021
★★ How can you gauge a site's authority when Google won't provide a clear method?
Google does not provide public documentation on measuring a site's authority, and there likely isn't a simple method for assessing this concept....
John Mueller Jan 22, 2021
★★★ How does Google determine the storage type for your pages in its index?
When building the index, Google uses signals like PageRank to estimate how frequently documents will be served (every second, once a week, or once a year) and uses different types of storage according...
Gary Illyes Jan 19, 2021
★★ How does Google really decide which pages to index?
Google uses the signals collected during earlier phases of indexing to decide whether or not a document should be indexed. This selection is a very sophisticated process that considers multiple factor...
Gary Illyes Jan 19, 2021
★★★ Is your content trapped on Google’s hard drive instead of in RAM?
Google uses different types of storage for its index based on the estimated frequency of service of documents. Documents likely to be served every second are stored in RAM, those that are less frequen...
Gary Illyes Jan 19, 2021
★★★ Can Submitting a Disavow File Actually Hurt Your Site in Google's Eyes?
John Mueller explained for the 2,476th time 😉 that submitting a disavow file to Google does not provide any negative signal to Google about the site that submitted it: "The disavow tool is a purely te...
John Mueller Jan 18, 2021
★★★ Why Does Google Flag a Redirected URL as Blocked by Robots.txt When It Actually Isn't?
SEO expert Glenn Gabe indicated on Twitter that, in Search Console, if URL A redirects to URL B which is blocked by robots.txt, URL A will be marked as also blocked by this file, even though, in reali...
John Mueller Jan 18, 2021
★★★ Why does Google refuse to index images without a parent HTML page?
Images can only be indexed by Google if they are part of an HTML page. An image sitemap works with the image extension that indicates which images are found on which HTML landing pages. Submitting onl...
John Mueller Jan 15, 2021
★★★ Should you really include HTML pages in an image sitemap instead of just JPG files?
Image sitemaps must reference the URLs of HTML pages that contain the images, with the image extension to indicate which images are present. Submitting only image files in a sitemap is ineffective, as...
John Mueller Jan 15, 2021
★★★ Should you really implement all Schema.org types to boost your SEO?
Google supports a subset of the Schema.org types. Focus on the rich result types listed in the Google Search documentation for visible effects. Other Schema.org types likely won't have any visible imp...
John Mueller Jan 15, 2021
★★★ How does Google really create its Search Console reports?
The development of reporting tools follows three stages: defining what can help a page succeed in search by checking crawling and content, building a pipeline to periodically review all pages in the i...
Daniel Waisberg Dec 28, 2020
★★ Has Google finally centralized all its SEO documentation in Search Central?
Google has undertaken a significant project to consolidate all its SEO documentation under a single site (Search Central), making it easier for webmasters who previously had to consult five or six dif...
John Mueller Dec 22, 2020
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