The process by which search engines execute JavaScript code to display and index dynamic content.
Why JavaScript Rendering Matters
JavaScript rendering is a critical part of modern SEO because a search engine’s crawler and a user’s browser are not the same. While a user’s browser is designed to execute JavaScript to create a rich, dynamic experience, a search crawler may not execute the JavaScript or may not wait for it to render, leading to a blank or incomplete page in the search index. This results in little to no organic traffic, as the website is essentially invisible to search engines. A failure to address these issues can cost a business millions in lost organic traffic and revenue.
Across Different CMS Platforms
The management of JavaScript rendering depends on your CMS and how you build your site.
WordPress
WordPress’s default structure is not a JavaScript-heavy site, so it is naturally SEO-friendly. However, if you are building a custom front-end with a JavaScript framework on top of a WordPress backend, you must use a server-side rendering (SSR) approach to ensure that your pages are crawlable and indexable.
Shopify
Shopify’s standard themes are also not JavaScript-heavy, which is great for SEO. If you are using a headless commerce approach with a JavaScript framework, you must use a server-side rendering approach to ensure all your product pages are crawled and indexed.
Wix
Wix has a closed system that is generally SEO-friendly. The platform’s system has been designed to handle its dynamic content in a way that is compliant with search engine guidelines, so you don’t typically need to worry about the technical side of JavaScript SEO.
Webflow
Webflow generates clean, semantic HTML that is highly SEO-friendly. While you can add your own JavaScript, the core content is always rendered on the server, which prevents the SEO issues commonly associated with a JavaScript-heavy site.
Custom CMS
With a custom CMS, you have the most control but also the most responsibility. You can build a system that is perfectly optimized for a search engine’s rendering budget by using a server-side rendering (SSR) approach. This is the most effective way to ensure that all your pages are rendered and indexed.
Across Different Industries
The management of JavaScript rendering is a concern for all industries that use dynamic content.
E-commerce
E-commerce sites often use a JavaScript framework for a fast and modern user experience. It is crucial to ensure that all your product and category pages are rendered and indexed, as a failure to do so can lead to a significant loss of organic traffic and sales.
Local Businesses
Local businesses may use a JavaScript framework for their website to create a fast and seamless user experience. It is crucial to ensure that their key pages, like their location, hours, and contact information, are easily crawlable and indexable for local search.
SaaS Companies
SaaS companies often use a JavaScript framework for their marketing pages and dashboards. It is crucial to ensure that their marketing pages are rendered and indexed, while their user dashboards can remain a client-side rendered application.
Blogs
Blogs built with a JavaScript framework can suffer from a limited rendering budget. It is critical for all articles to be rendered and indexed, which is a major factor in organic traffic.
Do’s and Don’ts of JavaScript Rendering
Do’s
- Do use a server-side rendering (SSR) or pre-rendering solution. This is the gold standard for JavaScript SEO.
- Do use the URL Inspection tool in Google Search Console. This tool will show you how Google sees your pages.
- Do ensure all your important links are in the HTML. This is a great way to ensure that a search crawler can find all your pages.
Don’ts
- Don’t use a pure client-side rendering (CSR) approach. This is the number one mistake and can lead to a page having little to no visibility in search results.
- Don’t block search engines from crawling your JavaScript files. A search engine needs to access your JavaScript to properly render the page.
- Don’t use a JavaScript-only pagination. This can lead to a significant portion of your content being invisible to search engines.
Common Mistakes to Avoid
- A lack of server-side rendering (SSR) or pre-rendering: This is the most common and devastating mistake.
- Discrepancies between the rendered and static HTML: Sometimes, a page that looks great to a user is a mess to a crawler. You must ensure that the rendered content is the same as the static content.
- Failing to check for crawling errors: Use Google Search Console’s URL Inspection and Coverage reports to check for crawling errors and fix them immediately.
FAQs
How does JavaScript rendering differ from a traditional HTML page?
A traditional HTML page is static, with all content in the initial file. A JavaScript-rendered page is dynamic, with the content being built in the user’s browser using JavaScript. A search engine must execute the JavaScript to see the content on a dynamic page.
Is JavaScript rendering a bad thing for SEO?
No, JavaScript rendering is not inherently bad. While it can pose challenges for search engines, it also allows for a better user experience with interactive and dynamic content. When implemented correctly with server-side rendering or pre-rendering, a website can have both a great user experience and be SEO-friendly.
What is the difference between client-side rendering (CSR) and server-side rendering (SSR)?
With CSR, the browser downloads a minimal HTML page and then uses JavaScript to build the rest of the content. With SSR, the server generates the full HTML page and sends it to the browser. For SEO, SSR is far superior.
How can I test if my website is rendered correctly for search engines?
The best way to test is by using Google’s URL Inspection tool in Google Search Console. It shows you a screenshot of how Google’s crawler sees your page and a list of any rendering issues it found.
Can a search engine miss content that is loaded with JavaScript?
Yes. If a search engine’s crawler cannot render and execute a page’s JavaScript, it may miss important content. This is why it is crucial to use a rendering method that ensures all your content is visible to search engines.
