What does Google say about SEO? /
This category compiles all official Google statements regarding JavaScript and technical aspects of search engine optimization. Modern JavaScript frameworks (React, Angular, Vue.js) and web application architectures (SPA, SSR, CSR) present critical challenges for crawling and indexing. Google's guidance on JavaScript rendering, dynamic DOM manipulation, AJAX implementation, and API calls is essential for ensuring client-side content visibility. SEO professionals will find authoritative positions on implementation best practices, differences between server-side and client-side rendering, and recommendations for optimizing load times while guaranteeing content accessibility to search crawlers. Understanding data formats (JSON, XML) and their SEO implications completes this vital resource. These official declarations help prevent common technical implementation mistakes that can severely impact the search performance of modern websites and JavaScript-powered applications. Access to Google's verified positions on these technical matters enables practitioners to make informed architectural decisions and implement JavaScript solutions that maintain strong organic search visibility while delivering enhanced user experiences.
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★★★ Is it true that AMP is a speed factor for Google?
AMP or non-AMP is not a speed criterion in itself: it is possible to create very fast pages without AMP and slow pages with AMP. Google measures the actual speed (future Core Web Vitals) of the versio...
John Mueller Aug 21, 2020
★★ Can the JavaScript History API really force Google to change your canonical URL?
When JavaScript uses the History API to change the URL after the page has loaded, Google may interpret this change as a redirect and choose the modified URL as canonical. This behavior depends on the ...
John Mueller Aug 21, 2020
★★ Why does Google make it impossible to use Search Console Insights without Analytics?
Google Search Console Insights combines data from Google Analytics and Search Console to provide a simplified view. Both data sources are required for the tool to function since it integrates informat...
John Mueller Aug 21, 2020
★★ Does the new structured data testing tool really take up to 30 seconds to analyze a page?
The new structured data testing tool takes longer (up to 30 seconds at times) than the old one (4 seconds) because it processes the page through the entire Google indexing pipeline, rather than just p...
John Mueller Aug 21, 2020
★★ Can a hacked site lose its crawl budget due to Google security alerts?
A hacked site with malware or phishing reported in Search Console will not see its crawl reduced. The impact is on display in the search results (warnings, filtering), not on the frequency or intensit...
John Mueller Aug 21, 2020
★★ Why is Google so tight-lipped about its indexing incidents?
The indexing incident on August 10 was resolved quite quickly, and Google has very little additional information to share publicly. The incident on August 15 appears to have been very brief. Google do...
John Mueller Aug 21, 2020
★★★ Do Core Web Vitals really measure what your users actually see?
For Core Web Vitals (a future ranking factor), Google measures the performance of the version of the page that users actually see: the AMP version if that’s what displays, the classic HTML version oth...
John Mueller Aug 21, 2020
★★★ Does Google really track HTML links that are hidden by JavaScript?
If an HTML link exists in the code but a JavaScript event captures the click (for example, to display a dropdown menu instead of navigating), Google can still see and follow that HTML link. The <a> el...
John Mueller Aug 21, 2020
★★★ Should you really add nofollow to footer links between sites of the same group?
If sites belong to the same company, there's no need to add the nofollow attribute to cross links in the footer. Google recommends linking primarily by brand name. For a handful of sites, it's no prob...
John Mueller Aug 21, 2020
★★★ Why does Google measure Core Web Vitals on the actual page version your visitors are really viewing?
For Core Web Vitals (a future ranking signal, announced at least 6 months in advance), Google will analyze the page that real users predominantly view (AMP or standard HTML depending on the user journ...
John Mueller Aug 21, 2020
★★★ Does Google Really Penalize Sites Listed in Disavow Files?
John Mueller has said it again for the 345th time 🙂: the fact that a website is listed in a disavow file submitted to Google by another site has no impact on its crawl or future rankings and does not ...
John Mueller Aug 17, 2020
★★★ Why does Google only index one language when your site switches through JavaScript?
If the site's language is managed solely by JavaScript/cookies (same URL for all languages), Google can only index one language version because Googlebot does not follow language switchers or use cook...
Johannes Müller Aug 14, 2020
★★★ Can you inject video tags via JavaScript without facing SEO penalties?
Google fully accepts that video tags and their metadata (poster image, etc.) can be injected by JavaScript instead of being present in the source HTML. If the tag is visible in the rendered HTML (veri...
Johannes Müller Aug 14, 2020
★★ Should you limit the number of outbound links to the same domain to avoid a Google penalty?
Having numerous outbound links to the same domain (e.g., Netflix for a movie list) is not problematic for Google as long as it adds value for the users. It is comparable to Amazon affiliate sites with...
Johannes Müller Aug 14, 2020
★★★ Is cross-domain duplicate content really harmless for your SEO?
Having the same content in the same language across multiple domains (e.g., English content on .com and .pl) is not penalized. Google simply chooses a canonical URL. If the content differs slightly (l...
Johannes Müller Aug 14, 2020
★★ Why does Google aggressively recrawl your site after a migration?
When Google detects significant changes on a site (URL structure change, domain migration), it may trigger an accelerated recrawl to quickly obtain an updated image. The site is neither paused nor rem...
John Mueller Aug 11, 2020
★★★ Should you really modify the lastmod of the sitemap to speed up recrawling after fixing missing tags?
After correcting pages missing title and meta description tags, the recommended method to speed up recrawling is to update the 'lastmod' date in the XML sitemap. This is not gaming: these pages have g...
John Mueller Aug 11, 2020
★★ Is it true that structured data makes a difference based on whether it's implemented with a plugin or manually?
Google accepts structured data implemented via a WordPress plugin, theme, manual code, or JavaScript after the page loads, with no preference. Only the validity of the final structured data counts. Fo...
John Mueller Aug 11, 2020
★★ Why does the mobile-friendly test produce conflicting results on the same page?
The mobile-friendly test can yield varying results (partially loaded, not mobile-friendly, mobile-friendly with missing resources) for the same page tested at different times. This happens because Goo...
John Mueller Aug 11, 2020
★★ Should you manually code your structured data or opt for a WordPress plugin?
Both approaches work perfectly. Google accepts structured data whether it comes from a plugin, a theme, a manual addition, or JavaScript after page load. From a practical standpoint, using a plugin al...
John Mueller Aug 11, 2020
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