What Cloudflare Workers is
Cloudflare Workers runs application code on Cloudflare's edge network, so the delivery edge and the application runtime are the same infrastructure. A Worker receives a workers.dev hostname and is usually served on a custom domain instead.
How DNSTrace.dev detects it
Detection correlates independent public signals. A single match is reported as strong evidence; agreement between a response header and the announcing network is reported as confirmed.
CNAME targets under workers.dev— The default Worker hostname a custom domain replaces.cf-ray with a Cloudflare server header— Present because a Worker answers from the same edge as the rest of Cloudflare's network.AS13335— The Cloudflare autonomous system announcing the address.
What a detection proves
The hostname is served from Cloudflare's network, and a workers.dev mapping indicates a Worker.
What it does not prove
A Cloudflare edge alone does not mean a Worker. A proxied site on any origin produces the same cf-ray and server header, which is why the workers.dev target is the distinguishing signal.
Common questions
How is this different from a proxied site?
A proxied site keeps its own origin behind Cloudflare. A Worker is the application, so there is no separate origin to reach.
Is Cloudflare Pages reported separately?
Pages and Workers are different products and a shared edge signal identifies neither on its own. Only the default hostname distinguishes them.
Compare with
VercelVercel, Inc.
Frontend application platform
NetlifyNetlify, Inc.
CDN, reverse proxy and WAF
CloudflareCloudflare, Inc.
Static hosting
GitHub PagesGitHub, Inc., a Microsoft subsidiary
Check a domain
Run a full lookup to see the delivery layer, the detected application stack, live TLS and the announcing network side by side.