JavaScript is a client-side programming language, which can make your webpages interactive and dynamic. As a client-side language, it’s processed in your computer and results are shown directly. As comparison, PHP is a server-side language with codes placed inside the server. After processing inside the server, HTML codes are made by the server and sent to your computer’s browser for rendering. You can insert JavaScript code into the HTML. This language has direct effect on the SEO performance of your website.
- Let search engines know about your JavaScript code: Robots.txt is essential for the crawling performance of search engine bots. Some sites prevent bots from detecting JavaScript code. It means that search engines don’t get the complete information about your website. In fact, the practice of intentionally hiding JavaScript from bots is known as cloaking. This causes bots to see your website in different way, compared to regular visitors.
- Don’t replace simple internal linking with on-click events: Internal linking is an important SEO method and it allows bots to navigate through your website. Simple internal links work the best and you shouldn’t replace them with on-click events in JavaScript code. A regular internal linking uses anchor tag inside the HTML document. This optimizes bots crawling and user experience, as well.
- Don’t use special characters in URL: Many JavaScript-dependent website uses fragment identifiers, such as hashbangs (#!) and hashes (#). Using special characters other than slashes and backslashes in URL isn’t recommended. Search engine indexing works best if your URL format is clean. It should contain plain text and major keywords of your webpage. If you want to use infinite scrolling feature, you should use pushState, so the URL will be automatically updated, when users reach specific parts of the webpage.
- Test website: Some JavaScript codes are quite comprehensive and complex, which make it more challenging for bots to crawl the site. By testing the website, you can determine whether it works well, regardless of the presence of your JavaScript code. Test a couple of page, by adding complex JavaScript code. Wait to see whether they are properly crawled and indexed by Google. If Google can’t crawl your JavaScript-rich website, you may need to work with a skilled development team to find out how it can be done.
- Remove site latency: When DOM is created using a HTML document, a majority of resources are loaded as commanded by the HTML document. If you have a big file before the HTML code, it will be loaded by the browser first. This could cause significant delay, if essential information appears only afterward. The key idea is to first process and display the most essential information to your users. It means that your most essential content must be located above the fold. JavaScript code is often placed at the upper portion of HTML document and if it’s large enough, the page load speed can be affected. If JavaScript code significantly blocks the rendering process, this is called the perceived latency. It means that your page can potentially load faster, but it’s slowed down by poorly optimized JavaScript code.