Can Search Engines Index JavaScript?

JavaScript gives the user an intuitive, dynamic, and interactive online experience. When crawling conventional HTML pages, everything is simple, and the procedure is quick. Googlebot may visit simultaneously after downloading an HTML file and extracting the source code's links. After downloading the CSS files, the page is indexed by Google's Indexer, which also receives all downloaded resources.

  • When crawling a website that mainly utilizes JavaScript, things become challenging. Googlebot downloads an HTML file.

  • Googlebot does not see links in the source code since they are only inserted after JavaScript has run.

  • Next, the CSS and JS files are downloaded. Googlebot must parse, build, and run JavaScript using the Google Web Rendering Service.

  • WRS retrieves the data from the database or other APIs.

  • The indexer may index the material. The Googlebot can then add the newly found links to its queue for further crawling.

This comes to webpage rendering. The process of converting HTML, CSS, and JavaScript code into the interactive webpage visitors anticipate seeing when clicking on a link is known as rendering a webpage. Every page of a website is created with the user in mind.

Rendering SEO

For both users and Google, parsing, building, and executing JavaScript files takes a lot of time. Google often can't index the content of a page with a lot of JavaScript until the website has been fully produced.

Not everything slower is in the rendering process. It also describes the method of finding new linkages. Google frequently has trouble finding links on pages with JavaScript-rich websites before the page is generated. JavaScript is a computer language that must be built before it can be used; any syntax that is incompatible with a particular JavaScript version will cause the build to fail.

The most recent Chrome version is the foundation of Googlebot. This indicates that Googlebot renders websites using the most recent version of the browser. Googlebot browses websites the same way a person would while using a browser. Googlebot, however, is not your standard Chrome browser. Googlebot rejects user requests for authorization (i.e., Googlebot will deny video auto-play requests). Across page loads, cookies, local storage, and session storage are removed. Google won't index your content if it depends on cookies or other locally saved information. Googlebot may decide not to download all the resources, but browsers always do.

Google considers canonical tag changes made using JS to be unreliable. Therefore, make sure your canonical URLs are in HTML and not JS. Although there is a potential that Google has already resolved this issue, one should not take a chance with SEO until sure.

Indexing JavaScript

Google has a fair understanding of JavaScript. However, JavaScript does take more work than ordinary HTML because the crawler tries to understand and rank billions of websites globally. It may occasionally suffer as a result of this.

Google claims that Googlebot crawls sites using JavaScript in two phases. The crawler will examine the HTML during its initial scan and use it to index the site. They will come back at a later time to display the necessary JavaScript. However, the material with HTML markup is shown on websites made with server-side rendering. Googlebot won't need to visit the site again to render the JavaScript on the page to correctly index the content because the primary content is already visible. This can dramatically improve the JavaScript SEO approach.

The content contained within the JavaScript will not be indexed rapidly due to the time difference between the first and second runs through a site. As a result, the material won't be taken into account when determining initial ranks, and it could take some time until Google notices changes and updates its results.

Because of this, businesses which employ JavaScript SEO should be sure to include as much crucial material as they can in the HTML of their website. They should write important information so crawlers can understand it immediately if they want it to count toward their ranking.

JavaScript is not rendered until the Googlebot makes a second pass around your website. As a result, some websites make the error of adding markups to the HTML that loads during Google's initial scan of the website, like the "no index" tag. This tag could stop Googlebot from visiting the site again to perform the JavaScript, which would subsequently prevent the site from being properly indexed.


As businesses utilize JavaScript to mark up their pages and make their websites more engaging for their visitors, it remains a crucial component of the internet. But for many, it's still important to comprehend how Googlebot and other crawlers interpret JavaScript and how it could interact with JavaScript SEO. JavaScript-based websites may now be parsed, rendered, and indexed by crawlers and search engines in the same way that HTML-based websites can. However, it is the responsibility of the developers to make their websites accessible and crawlable as well as to comprehend how SEO for contemporary JavaScript websites functions.