What Google Really Thinks About JavaScript, Rendering & SEO
Martin Splitt from Google recently shared deep insights that help developers and SEOs make smarter decisions when building modern websites. His discussion clarified how Googleβs systems handle JavaScript, structured data, and the ongoing debate between server-side and client-side rendering.
π€ How Google Reads JavaScript Today
In a recent talk with Kenichi Suzuki of Faber Company Inc., Splitt explained how Googleβs AI systems, including Gemini, process JavaScript. Both Gemini and Googlebot use the same Web Rendering Service (WRS) to understand websites.
βGemini also rendersβ¦ Itβs basically like we have a service Googlebot uses, and Gemini uses the service as well,β he explained.
This makes Googleβs AI-based tools better at understanding JavaScript-heavy sites compared to other crawlers.
Some studies claim rendering delays can stretch over days. But Splitt cleared that up:
βThe 99th percentile is within minutes.β
So, unless something is seriously broken, most JavaScript content is rendered almost immediately.
π SSR or CSR? Pick the Tool That Fits
A lot of people want to know which is better: Server-Side Rendering (SSR) or Client-Side Rendering (CSR). Martinβs answer? It depends.
βDo you need a hammer or do you need a screwdriver?β
Hereβs the gist:
- SSR is great for blogs, articles, and other content-focused sites. It loads faster and is easier for crawlers.
- CSR is better for interactive web apps, like design tools or dashboards that need a lot of user input.
If your site is built to inform, go SSR or even use pre-rendered static HTML. If your site is built to do things, CSR may be the way to go.
π§© Structured Data: Helpful, Not a Ranking Hack
Martin also addressed structured data. Yes, it helps Google understand your site better. No, it doesnβt magically boost your ranking.
βIt gives us more information and more confidence in the content,β he said.
So while itβs not a direct ranking factor, it does support how your content appears in AI-driven results. And that matters more as AI continues to shape the future of search.
π Quick Recap You Can Use
Hereβs what you should keep in mind:
- Googleβs rendering engine handles JavaScript fastβoften in minutes.
- SSR helps content-focused sites load faster and rank better.
- CSR fits dynamic apps where the browser does most of the work.
- Structured data helps Google understand your content, even if it doesnβt help you rank higher.
π¬ Final Words from Googleβs Martin Splitt
Martin wrapped up the discussion with advice that every SEO should live by:
βThink about your users. Figure out what is your business goal, how to make users happy, and then just create great content.β
π Did You Know?
Google’s AI crawler and Googlebot use the same system to understand your site. But other search engines might notβso SSR can help make your site visible across the board.