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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★★ Should you really split your JavaScript bundles by site section for better SEO?
Rather than using a single massive JavaScript bundle, it's advised to split the bundles according to the logical sections of the site (blog, forum, shop) to avoid downloading unnecessary code and to i...
Martin Splitt May 27, 2020
★★★ Is dynamic rendering with expanded accordions considered cloaking by Google?
Serving Googlebot a version with expanded navigation accordions or without cookie banners via dynamic rendering is not considered cloaking, as long as the user is not misled about the main content. Th...
Martin Splitt May 27, 2020
★★★ Is the first wave / second wave model of JavaScript rendering still relevant?
The concept of 'first wave' and 'second wave' was a simplification to explain the crawling and rendering process. Google no longer uses it because it is misleading. The median time between crawling an...
Martin Splitt May 27, 2020
★★ Why does Googlebot still crawl using HTTP/1.1 instead of HTTP/2?
Googlebot still uses HTTP/1.1 for crawling. JavaScript optimization strategies must take this limitation into account, even though HTTP/2 offers multiplexing advantages for modern browsers....
Martin Splitt May 27, 2020
★★★ Should you really choose server-side rendering over dynamic rendering?
Google recommends server-side rendering over dynamic rendering because it creates faster sites for users. If implementation effort is required, it's better to favor the solution that also benefits use...
Martin Splitt May 27, 2020
★★★ Does Google really ignore Cache-Control headers for crawling?
Google generally ignores Cache-Control headers because many resources are under-cached. To force re-downloads, it's better to use versioned URLs with hash (e.g., app.abc123.js) rather than relying on ...
Martin Splitt May 27, 2020
★★★ Do JavaScript links really need to be <a> elements with href to be crawled?
For Google to follow links generated by JavaScript, they must be genuine <a> elements with a valid href attribute. Buttons, divs, spans with onclick, or <a> tags without href or with empty href are no...
Martin Splitt May 27, 2020
★★★ Is it really true that JavaScript-rendered content can be indexed by Google without any friction?
If the content appears in the 'Rendered HTML' tab of testing tools (Mobile-Friendly Test, Rich Results Test, URL Inspection Tool), it is correctly indexable by Google, even if it is not in the origina...
Martin Splitt May 27, 2020
★★★ Should You Create Your XML Sitemap Manually or Use an Automated Tool?
John Mueller explained on Reddit that, for large-scale websites, creating XML Sitemap files manually is not recommended, but rather using a tool (plugin or otherwise) from the CMS being used......
John Mueller May 25, 2020
★★★ Will Google Penalize Your Pages After Removing a Noindex Tag?
John Mueller explained on Twitter that a page that was initially deindexed via a meta robots "noindex" tag and then had this tag removed at a later time returns to a "normal" indexation situation afte...
John Mueller May 25, 2020
★★★ How can you effectively manage 404 errors in a SPA without risking deindexation?
For SPAs with client-side routing, Google recommends three solutions to signal a 404 error: redirect to a server URL with a 404 code, add a noindex tag, or use a soft 404 (automatically detected but l...
Martin Splitt May 18, 2020
★★ Does dynamic rendering really slow down your server or enhance your crawl budget?
Dynamic rendering generally takes more time on the server side because an additional rendering step is added. However, it can save client-side API requests and potentially increase the crawl budget fo...
Martin Splitt May 18, 2020
★★★ Should You Noindex Your XML Sitemap to Optimize Crawl Budget?
Frédéric Dubut (Bing), followed by John Mueller (Google), explained on Twitter that there is absolutely no problem with setting an XML Sitemap file to "noindex" (via the HTTP header) and that the URLs...
John Mueller May 18, 2020
★★★ Can Googlebot really crawl hidden links in a hamburger menu?
If a mobile navigation only appears in the DOM after user interaction (clicking on the hamburger), Googlebot will not see these links. The links must be present in the DOM, even if they are visually h...
Martin Splitt May 18, 2020
★★★ Is dynamic rendering really risk-free for SEO?
Serving identical or similar content to bots without JavaScript is not seen as cloaking. If the content varies slightly, it is dynamic rendering, which is perfectly acceptable according to Google....
Martin Splitt May 18, 2020
★★★ Is it true that hidden content in accordions is actually indexed by Google?
Content hidden behind accordions or tabs is indexable by Google as long as it is present in the DOM, even if it is invisible. However, the main content should not be hidden behind user interaction, an...
Martin Splitt May 18, 2020
★★★ Why does Google treat JavaScript redirects as 302s instead of 301s?
Google treats client-side JavaScript redirects as temporary redirects similar to 302s, not as permanent 301s. It's preferable to avoid them, but not critical if necessary....
Martin Splitt May 18, 2020
★★ Should you really use different domain names for a multilingual site?
For a multilingual site, it is acceptable to use different domain names according to countries (e.g., brand.se for Sweden, example.fr for France) instead of having all versions under a single domain. ...
John Mueller May 15, 2020
★★ Do temporary 404 errors during a migration really kill your SEO?
If pages return temporary 404s during a migration (for a few days) before redirects are set up, Google will recrawl the URLs, see the redirects, and treat them normally. The impact on ranking will be ...
John Mueller May 15, 2020
Should you encode non-ASCII characters in XML sitemap URLs?
URLs in an XML sitemap can contain non-ASCII characters. You just need to respect the encoding specified in the sitemap specification....
John Mueller May 15, 2020
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