Prerender

What is Prerender?

About

Prerender is a web crawler that pre-renders Single Page Applications (SPAs) into static HTML to improve SEO visibility for JavaScript-heavy websites and search engine indexing. You can see how often Prerender visits your website by setting up Dark Visitors agent analytics.

Expected Behavior

SEO (Search Engine Optimization) crawlers do not adhere to a fixed visitation schedule for websites. The frequency of visits varies widely based on several factors, including the search keywords it ranks for, and how many other websites link to it.

Type

SEO Crawler

Discovers search engine optimization insights

Detail

Operated By	Prerender, LLC
Last Updated	3 hours ago

Insights

Top Website Robots.txts

0% of top websites are blocking Prerender

Learn How →

Country of Origin

Germany

Prerender normally visits from Germany

Global Traffic

See All Global Bot & LLM Insights →

The percentage of all internet traffic coming from SEO Crawlers

Get These Insights for Your Website

Use the WordPress plugin, Node.js package, or API to get started in seconds.

Set Up Agent Analytics

Robots.txt

Should I Block Prerender?

Probably not, especially if you benefit from an SEO service yourself. However, you might choose to block them if you're concerned about things like server resource usage.

How Do I Block Prerender?

⚠️ Manual Robots.txt Edits Are Not Scalable

New agents are created every day. Instead, serve a continuously updating robots.txt that blocks new agents automatically.

Set Up Automatic Robots.txt

You can block Prerender or limit its access by setting user agent token rules in your website's robots.txt. Set up Dark Visitors agent analytics to check whether it's actually following them.

User Agent String Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) HeadlessChrome/137.0.0.0 Safari/537.36 Prerender (+https://github.com/prerender/prerender)

# robots.txt
# This should block Prerender

User-agent: Prerender
Disallow: /