Ethan Smith Q&A On How Using JavaScript Impacts SEO With Page Rendering

6 Dec 2024 · 2 min

Watch on YouTube

2:20

Ethan Smith explains how JavaScript rendering affects SEO. Google crawls pages twice: first without scripts, then with them. If the server version looks complete, Google may skip the JavaScript pass, leaving client-rendered content like reviews unindexed. Test what Google indexed by searching site:URL with exact quotes from client-side modules.

Questions this video answers

Short answer: No, it’s fine if implemented correctly. Server‑side rendering has no issue. Client‑side rendering can cause problems depending on how it’s done, especially with progressive loading or hybrid rendering.

Google performs two passes: first a non‑script, server‑side fetch, then a JavaScript‑enabled fetch. If the first pass appears complete, Google may skip the second, causing client‑side modules (e.g., reviews) to be missed.

Use a site:URL search with an exact quoted snippet from the client‑side module. If the snippet appears in search results, Google has indexed it; if not, it hasn’t.

Chapters

Ethan, I wanted to ask you about the use of JavaScript to render on page. Does that still inhibit the ability for crawlers to access content? And then does it inhibit maybe rankings from the lack of being able to assess the quality of that content? So just wanted your perspective on that.
Short answer is no, it's totally fine. Here's the long answer. So it depends on how you implement it. If you implement stuff server side, there's no issue. That's all fine. If you're implementing stuff client side, it depends on how you're doing it. So if you're progressively loading stuff on the page, Google might not see it. And sometimes what'll happen is, and also if you're doing a combination of server and client, that can cause problems. So Google does 2 passes of crawl to your site. The first is a without script server side. call. And the second is a client-side JavaScript call. If Googlebot thinks that it's got all the information on the server-side crawl, it will not, sometimes it will not crawl the client-side crawl. So I'll give you an example of that. It's common to have a product page where the photo description is loaded server-side and then the reviews are loaded client-side. And Google looks at the page without the reviews and thinks they got everything that needed and ignores the reviews. Does not do the client-side call. So when you have hybrid rendering, the client-side stuff might get missed. And you can verify that by doing site:URL and then do, take a snippet from your client-side module and then put it in quotes. So site:product page URL, and then quote, review snippet, quote. And then if there's no, if Google doesn't have it, then it didn't find it. And if they do, then it did. But the hybrid stuff can cause problems. And then depending on, you know, if you're progressively loading in multiple modules client side, it's possible that Google is also seeing some but not all. So you could do the exact same check, site colon and then URL and then exact match snippet in quotes from each of the modules. And then you can see whether or not it's getting crawled.