CDN Detector

About CDN detector

CDN Detector fingerprints the content delivery network or web application firewall in front of a site by reading its response headers and following its CNAME chain. It lists the evidence for each match so you can judge how strong it is, and it covers Cloudflare, CloudFront, Fastly, Akamai, Vercel, Netlify and others.

How to use it

1. Enter the domain, such as example.com, in the Domain box.
2. Press Detect CDN. Our server requests the site over HTTPS while it follows the CNAME chain of the name.
3. Read the badge and summary at the top: the primary vendor, or No CDN detected.
4. Open Evidence to see each matching header or CNAME with its vendor and kind: CDN, WAF, Cache or Platform.
5. Check Response, CNAME chain and Response headers for the raw data behind the verdict.

A site fronted by Cloudflare

Headers cf-ray: 8a1b-LHR and server: cloudflare, CNAME to example.com.cdn.cloudflare.net

Primary: Cloudflare. Evidence: two header matches and two CNAME matches, four signals in total. Summary: Cloudflare is fronting this site, based on 4 matching signals.

When to use it

• Learning which CDN a competitor uses before you compare performance.
• Confirming a migration to a new CDN by checking for its headers and CNAME.
• Finding out whether a site is behind a WAF when a scan is being blocked.
• Understanding why a site's IP address belongs to a CDN and not the hosting company.

Questions about CDN detector

How reliable is the verdict?

It is inference. A vendor-specific header like cf-ray is strong, while a generic one such as x-varnish only shows something caches. That is why the evidence is listed, so you can weigh each signal.

Why does it say no CDN when I am sure there is one?

Some proxies strip identifying headers or use custom names. A site can also use a CDN only for assets, on a different hostname, so the main domain would show nothing.

Can it show multiple vendors?

Yes. Stacked layers such as a WAF over a CDN are common, and every vendor with evidence is listed. The primary is the first non-cache match in a priority-ordered list of about fifteen signatures.

Is the page downloaded?

Only the headers are read. The body is discarded right away. The request is made by our server, so the domain is sent to it, and redirects are followed up to 5 hops.

How many CNAME hops are followed?

Up to five hops are followed, and the chain shown is the sequence of alias targets. Each detection run also counts toward a limit of roughly 20 per minute per visitor.

Related tools

• HTTP Headers LookupLook up HTTP headers for a URL
• IP LookupLook up information about an IP address
• DNS LookupLook up DNS records for a domain
• WHOIS LookupLook up WHOIS information for a domain
• PingPing a domain or IP address
• SSL LookupLook up SSL certificate information for a domain