Single page application SEO

A single page application builds its pages in the browser with JavaScript, so the HTML your server sends is close to empty. Google renders JavaScript and can index a well-built SPA, but the major AI crawlers do not run JavaScript, so they need finished HTML from server rendering, prerendering or a prerender service.

<body>
  <div id="root"></div>
  <script src="/app.js">
</body>

SPA SEO in five rules

The problem: two kinds of crawlers

Google renders, with a delay. Google processes JavaScript apps in three phases: crawling, rendering and indexing. Pages with a 200 status go into a render queue, and "once Google's resources allow, a headless Chromium renders the page". Vercel and MERJ measured the delay on nextjs.org in April 2024: median 10 seconds, 90th percentile about 3 hours, 99th percentile about 18 hours.

AI crawlers do not render at all. Vercel and MERJ found that "none of the major AI crawlers currently render JavaScript". This covers OpenAI (GPTBot, OAI-SearchBot, ChatGPT-User), Anthropic (ClaudeBot), Meta, ByteDance and Perplexity. They read what the server sends, and for an SPA that is an empty root element. Gemini and AppleBot are exceptions that render.

This matters more each year. Cloudflare reported that GPTBot requests rose 305% and ChatGPT-User requests 2,825% from May 2024 to May 2025.

The result: an SPA can rank on Google and be invisible to ChatGPT, Claude and Perplexity. Your site looks fine in every browser, so you do not notice. Read more on how AI crawlers see your site and whether ChatGPT can read JavaScript.

How to check your SPA

1. Free checker. Enter a URL to compare the page without JavaScript and in a real browser.

See what ChatGPT sees on your site

2. Raw HTML. Fetch a deep URL, not only the home page.

curl -s https://www.<your-domain>/pricing | grep -o "<title>.*</title>"
curl -s -o /dev/null -w "%{http_code}\n" https://www.<your-domain>/this-page-does-not-exist

The first line shows the title crawlers get without JavaScript. If every route shows the same title, it comes from your static index.html. The second line should print 404. Many SPAs print 200 because the server returns index.html for every path.

3. Google. Use the URL Inspection tool or the Rich Results Test to see the HTML Google rendered.

Your options

Server-side rendering or static generation

Move the app to a framework that renders HTML on the server or at build time. For React, the React team recommends Next.js or React Router. Vue, Angular and Svelte have their own options.

Best when you are starting out or rebuilding anyway. It is the most complete fix, and Google recommends "server-side rendering, static rendering, or hydration" as the long-term solution. It costs a migration and, for server rendering, a host that runs server code.

Build-time prerendering

A tool crawls your built app and saves one HTML file per route. Best for small sites with few routes that change only on deploy. Routes created from live data are missing until the next build. See the React SEO guide for react-snap.

A prerender service

A service renders your pages in a real browser when a crawler asks and serves the HTML from a cache. People still get the SPA. Google calls this dynamic rendering, a "workaround and not a long-term solution", and says that with similar content it is not cloaking.

Best when you have a working SPA, many routes or frequently changing content, and no plan to migrate soon.

Meta tag libraries alone

React Helmet, vue-meta and similar libraries set titles and descriptions from JavaScript. They help Google after rendering, but they do not put content or tags in the HTML that AI crawlers receive. Use them together with one of the options above.

When Prebaked is the right choice

Prebaked is a prerender service for SPAs that already work for people and should also work for crawlers.

• No rewrite: add a snippet for nginx, Netlify, Cloudflare or another platform.
• AI crawlers included: the bot list covers GPTBot, OAI-SearchBot and ClaudeBot as well as search engines.
• Same content for everyone: Prebaked renders your page as it is. No content is added or changed for bots.
• Correct status codes: a page that renders as a 404 returns 404 to crawlers, and pages can set their status with a prerender-status-code meta tag.
• Never worse than today: if Prebaked is slow or unavailable, crawlers get your original page.
• Cache hits are free. Warm the cache from your sitemap so crawlers get cached pages.

Prebaked does not fix thin content, duplicate titles or broken links. It makes sure crawlers receive the page your visitors see.

FAQ