Free JavaScript SEO Checker
See what Google and AI crawlers get before JavaScript runs: content, title, canonical, links, render-blocking and blocked scripts, frameworks and JS-only images – with clear fixes for client-side rendering problems.
What is a JavaScript SEO Checker?
A JavaScript SEO checker analyses the raw HTML a server sends – the version crawlers see before any JavaScript runs – and checks whether the important SEO elements are already there: main content, title, meta description, canonical, headings and crawlable links.
Google renders JavaScript in a second, delayed step, and most AI crawlers such as GPTBot, ClaudeBot and PerplexityBot do not run JavaScript at all. Content, links or tags that only appear after JavaScript runs may never be indexed or cited.
What the JavaScript SEO Checker checks
Every problem comes with plain-English steps to fix it, and every result is added to your downloadable Technical SEO report.
Word count and full text crawlers see without JavaScript.
Title, meta description, canonical and H1 before rendering.
Real <a href> links vs onclick, data-href and #! URLs.
Render-blocking scripts, inline JS size and script count.
Own scripts disallowed in robots.txt.
React, Vue, Angular, Next.js, Nuxt and more.
How to use the JavaScript SEO Checker
Click Load Example above to see a real result first.
Enter a page URL
Choose a page that is built with JavaScript or is not getting indexed.
Click “Check JavaScript SEO”
The tool downloads the raw HTML without running JavaScript.
Read the “Fix first” tab
Content and tags that depend on JavaScript come first.
Look at “Raw HTML text”
This is what AI crawlers and the first Google pass see.
Common problems and how to fix them
| Problem | Why it matters | How to fix it |
|---|---|---|
| Empty app shell | Nothing to index without rendering. | Use SSR or static generation. |
| Links via onclick | Pages are not discovered. | Use <a href> links. |
| Title/canonical set by JS | Unreliable signals. | Output them in the server HTML. |
| JS blocked in robots.txt | Google renders a blank page. | Allow your script files. |
| JS-only lazy images | Images not indexed. | Use native loading=”lazy”. |
Frequently asked questions
Can Google index JavaScript content?
Yes, Google renders JavaScript with an evergreen Chromium, but rendering is queued, costs resources and can fail. Server-rendered content is indexed faster and more reliably.
Do AI crawlers run JavaScript?
Most do not. GPTBot, ClaudeBot and PerplexityBot mainly read the raw HTML, so client-side-only content is invisible to AI search answers.
Is WordPress good for JavaScript SEO?
Yes. WordPress outputs server-rendered HTML. Problems usually come from heavy page-builder scripts or plugins that load content with JavaScript.
What is dynamic rendering?
Serving pre-rendered HTML to bots and JavaScript to users. Google calls it a workaround, not a long-term solution; SSR or static rendering is preferred.
How do I see the rendered HTML Google uses?
Use URL Inspection in Google Search Console and click “View crawled page” or “Test live URL”.
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Built and maintained by the AM Digital Marketing Agency SEO team. Last updated: .
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