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Which AI crawlers actually execute JavaScript?

This page carries three blocks of text. One is in the HTML. Two exist only if JavaScript runs. Every request is logged at the network edge, before any rendering happens, so a crawler that reads the HTML and skips the script leaves a visible gap. The log is public, below.

Block A — server-rendered HTML

This sentence is present in the raw HTML response. Every crawler that requests this URL can read it without running any code.

Block B — injected by JavaScript

Waiting for script execution…

Block C — fetched from the server by JavaScript

Requesting random text…

How to read the log

  • edge means the bot requested the page. This is recorded before rendering, so it captures every crawler.
  • js-fetch means the bot ran the script and called back to the server. Only renderers appear here.
  • A bot with edge hits and zero js-fetch hits read the HTML and ignored the JavaScript. That is the finding this page exists to measure.
  • ✓ marks a request whose network operator matches the vendor it claims to be. User agents are trivially spoofed, so unverified hits are shown but should not be trusted.

No IP addresses, cookies or visitor identifiers are stored. The log keeps the user agent, request path, bot label, network operator and country only.