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How Do Search Engines Crawl And Index JavaScript?


Google, although being the most popular and trusted search engine, and the biggest of all, has problems while crawling and indexing JavaScript-rich websites! Google can only index very few JavaScript frameworks out of the entire lot. Now imagine, if Google being such a huge search engine, has problems with JavaScript crawling and indexation, how do the smaller search engines deal with this problem? And if this is the case, will having JavaScript websites mean complete de-indexation? As far as it can be seen, if you decide to set up a website where Google bots need to process JavaScript before seeing the HTML, you are definitely risking your chances with Google and other search engine rankings.

Although Google and Ask can index JavaScript-generated content to quite some extent, other search engines like Yahoo!, AOL, Bing, and Yandex can not at all index JavaScript, meaning that they won’t be able to see your content if it isn’t HTML. Now, Google and Ask cover only a little more than 60% of the entire search engine market, with Ask covering only 1%. So, what about the remaining 40%? Is your JavaScript-rich website going to cost you 40% of your site’s visibility on SERPs? Let us take a detailed look at how search engines deal with JavaScript.

Do you know that Yahoo! and AOL have been available even before Google? But yet, they fall behind when it comes to crawling and indexing; the main reason being the high costs associated with the process. Google can invest millions into the process without worrying about the ROI; and that is pretty obvious. But, what about Ask? How is it possible that Ask can also invest in crawling and indexing JavaScript with only 1% of the market share? The fact here is that Ask’s crawling is using Google’s technology; and this has been ever seen since the Google-Ask relationship after Google’s Penguin update in 2012. Now, speaking about other search engines, the only content that they can index properly is the 100% HTML page.

Even if your target market is heavily dominated by Google, JavaScript crawling and indexing is still at an early stage. Therefore, if you wish to see significant traffic improvement, you may as well shift from JavaScript-driven pages to non-JavaScript ones. However, this doesn’t mean that JavaScript isn’t great. JavaScript is awesome and is great for SEO, but what it requires is experience and close attention to best practices. If you want to enjoy all the perks of JavaScript without worrying about any ranking problems, you can work on using isomorphic JavaScript, which can run both client-side and server-side, with the back-end and front-end sharing the same code. Therefore, you can enjoy dynamic and beautiful websites without having to worry about SEO.

However, if you don’t want to risk it yet until the search engines learn how to deal with JavaScript-rich websites, you can as well stick to HTML and CSS on the front-end. Nonetheless, whatever kind of format and coding you are looking for, you can always hire professional SEO services in India to help you do the job just perfectly, so that you have no ranking and SEO problems.


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