The web is in a golden age of front-end development, and JavaScript and technical SEO are experiencing a renaissance. As a technical SEO specialist and web dev enthusiast at an award-winning digital marketing agency, I’d like to share my perspective on modern JavaScript SEO based on industry best practices and my own agency experience. In this article, you'll learn how to optimize your JS-powered website for search in 2021.
What is JavaScript SEO?
JavaScript SEO is the discipline of technical SEO that’s focused on optimizing websites built with JavaScript for visibility by search engines. It’s primarily concerned with:
- Optimizing content injected via JavaScript for crawling, rendering, and indexing by search engines.
- Preventing, diagnosing, and troubleshooting ranking issues for websites and SPAs (Single Page Applications) built on JavaScript frameworks, such as React, Angular, and Vue.
- Ensuring that web pages are discoverable by search engines through linking best practices.
- Improving page load times for pages parsing and executing JS code for a streamlined User Experience (UX).
Is JavaScript good or bad for SEO?
It depends! JavaScript is essential to the modern web and makes building websites scalable and easier to maintain. However, certain implementations of JavaScript can be detrimental to search engine visibility.
How does JavaScript affect SEO?
JavaScript can affect the following on-page elements and ranking factors that are important for SEO:
- Rendered content
- Links
- Lazy-loaded images
- Page load times
- Meta data
What are JavaScript-powered websites?
When we talk about sites that are built on JavaScript, we’re not referring to simply adding a layer of JS interactivity to HTML documents (for example, when adding JS animations to a static web page). In this case, JavaScript-powered websites refer to when the core or primary content is injected into the DOM via JavaScript.
This template is called an app shell