JavaScript renderability checker

AI crawlers do not run JavaScript. If your content only appears after the browser renders it, ChatGPT, Perplexity and Claude never see it. This checker shows you what they actually get.

Check your siteHow scoring works

5 checks · 1 critical gate · 15% of the Slurp Score

Why it matters for AI search

The Vercel and MERJ study measured it directly: GPTBot downloads JavaScript files but never runs them. Same for ClaudeBot and PerplexityBot. Only Googlebot renders. A client-side React, Vue or Angular app hands every AI crawler an empty shell.

You cannot spot this in a browser, because you always see the finished page. GetSlurp reads the raw HTML instead: how many words it contains, whether it is just a framework shell, and how much of the page is code versus content. The Chrome extension goes one further and compares the raw HTML against the rendered page in your tab.

What GetSlurp checks

This list comes straight from the audit engine, so it always matches what the extension and MCP server actually run.

render.content-in-raw-htmlGate

No major AI crawler executes JavaScript (GPTBot, ClaudeBot and PerplexityBot all parse static HTML only), so content that exists only after client-side rendering is invisible to every AI answer engine.

Fix: Server-render the page (SSR or static generation) so the main content is present in the initial HTML response.

render.ssr-verdictGraded

A JS framework is fine when it server-renders. The risk is a client-only app shell that hands crawlers an empty page.

Fix: Enable SSR/SSG for content routes (e.g. Next.js App Router server components, Nuxt SSR) instead of client-only rendering.

render.text-ratioGraded

A very low text-to-markup ratio means crawlers spend their budget parsing code instead of content, and extraction quality drops.

Fix: Reduce markup bloat and inline scripts on content pages; move large scripts to external files.

render.dom-sizeGraded

Very large DOMs slow crawler processing and dilute passage extraction.

Fix: Keep pages under ~1,500 DOM elements; paginate or trim decorative wrapper elements.

render.rendered-diffInformational

The definitive renderability test compares raw HTML against the browser-rendered DOM; this run used static analysis only.

Fix: No action needed. Run GetSlurp with a headless browser available for the full raw-vs-rendered diff.

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