Client-side rendering
Building the page in the visitor's browser with JavaScript instead of sending finished HTML. Crawlers that do not run scripts see an empty shell where your content should be.
Updated August 21, 2026
Plenty of AI crawlers fetch raw HTML and never execute JavaScript. If your content only exists after the scripts run, those crawlers see a blank page and move on — and you will not get an error, just silence. Testing this is easy: fetch your own page without JavaScript and read what comes back. Whatever is missing is invisible to a meaningful share of the machines you are trying to reach.
Related terms
- Technical accessibility. Whether a machine can fetch and read your page at all: status codes, response speed, robots rules and content that exists without JavaScript. It is the precondition for every other signal.
- Crawler (bot). An automated program that fetches web pages. Search engines and AI systems use crawlers to read the web. Crawlers read the raw page and often do not run all of a site's scripts.
- Retrieval. The step where a system finds and fetches your page. If a page is blocked, unreachable, or clearly not about the topic asked, it is never retrieved, and nothing else matters.