JavaScript visibility checker
See what a crawler sees when your JavaScript has not run yet.
Free, instant, and nothing to sign up for.
This checked one thing. A full audit reads the whole site and tells you what to fix first.
Run the free auditWhat this checks
- How much readable text exists before any JavaScript executes
- Whether the title, H1 and H2s are present in the raw HTML
- Whether the page is an empty app shell waiting to hydrate
- A visibility score and band, with the flags behind it
Why it matters
Google renders JavaScript, but rendering is queued, budgeted and not guaranteed, and most AI crawlers do not run JavaScript at all. A site built as a single-page app can look perfect in a browser and arrive at an answer engine as an empty div. This is the check that explains an otherwise inexplicable pattern: a good-looking site that ranks for nothing and is never cited.
How to read the result
Use View Source rather than Inspect, or the result is meaningless: Inspect shows the DOM after hydration, which is the thing being tested. A high score means your content is in the HTML and every crawler can read it. A low score with an empty shell root means your content exists only after JavaScript, so you are relying on rendering that AI crawlers will not do for you.
Common questions
Does Google not render JavaScript?
It does, in a second pass, when it has capacity. That is fine for a large trusted site and unreliable for a small one. Every page that needs rendering competes for a budget you do not control.
Do AI crawlers run JavaScript?
Generally no. They fetch the HTML and read it. If your content is not in the raw HTML, it does not exist as far as most answer engines are concerned, whatever Google eventually manages to index.
How do I fix a low score?
Server-side rendering or static generation, so the HTML arrives complete. On WordPress and most site builders this is already the default and the score should be high. If yours is low, the framework is the thing to look at.
Other free checks
Each one answers a different question about the same page.