CDN Checker — Instantly Detect Any Site's CDN

Paste a URL. Find out whether the site uses Cloudflare, Fastly, Akamai, AWS CloudFront, Vercel, Netlify, or another CDN. Free, instant, no signup.

Try: github.com · stripe.com · shopify.com · vercel.com

CDNs This Checker Detects

DetectZeStack identifies every major CDN and edge platform — plus hosting providers that double as CDNs.

CloudflareHeaders, DNS, IP ranges
FastlyHeaders, DNS CNAME
AkamaiHeaders, edgekey.net DNS
AWS CloudFrontHeaders, cloudfront.net DNS
Amazon S3Static asset hosting
VercelHeaders, vercel.app DNS
NetlifyHeaders, netlify.app DNS
Bunny.netb-cdn.net DNS
KeyCDNkxcdn.com DNS
Google Cloud CDNgoogleusercontent.com
Azure CDNazureedge.net DNS
StackPathstackpathdns.com
BunnyCDNb-cdn.net DNS
jsDelivrcdn.jsdelivr.net
Impervaincapdns.net DNS
+ 100 morevia DNS / TLS signatures

How It Works

The checker combines three signals so it catches CDNs even when one of them is hidden.

HTTP headersserver, via, x-cache, cf-ray, x-amz-cf-pop, x-served-by — most CDNs leak themselves here.
DNS CNAME recordscdn.cloudflare.net, cloudfront.net, fastly.net, edgekey.net — proves edge routing even when headers are stripped.
TLS certificate metadataIssuer + SAN patterns identify shared-cert CDNs (Cloudflare Origin CA, Amazon Trust Services, etc.).

Need This in Code? Use the API

Same detection, programmatic — script your CDN audits, monitor migrations, enrich CRM records.

curl "https://detectzestack.com/analyze?url=stripe.com" \
  | jq '.categories.CDN, .categories.PaaS'

# Output:
# ["Amazon S3"]
# ["Amazon Web Services"]

100 requests/month free on RapidAPI. Paid plans from $9/month for 1,000 requests. Full docs: OpenAPI spec.

Frequently Asked Questions

How do I check what CDN a website uses?

Paste the URL into the checker at the top of this page. It inspects HTTP response headers, DNS CNAME records, and TLS certificate metadata to identify the CDN provider in a few seconds.

Is this CDN checker free?

Yes — the on-page checker is free and requires no signup. For bulk or programmatic CDN detection, the DetectZeStack API offers a free tier (100 requests/month) with paid plans from $9/month.

Can a site use more than one CDN?

Yes. Many large sites use multiple CDNs — Cloudflare for the main domain, CloudFront for S3-hosted assets, a separate CDN for video. The checker lists every CDN it detects, not just the primary one.

Does the checker work on sites behind authentication?

Yes for the login wall itself, which is still served by whatever public CDN the site uses. Internal-only domains aren't reachable from our server.

How does CDN detection actually work?

Three signals combined: (1) HTTP headers like cf-ray, x-amz-cf-pop, x-cache, via; (2) DNS CNAME chains pointing to known CDN edge networks; (3) TLS certificate issuer and SAN patterns. The detector falls back through all three so it catches CDNs even when headers are stripped.

Why doesn't my site show its CDN?

Some sites proxy through their own infrastructure before hitting the CDN, which can strip headers. If your DNS CNAME points directly at a CDN edge network, that's usually enough — try the DNS lookup tool to inspect the chain directly.

Detect CDNs Programmatically

100 free API requests per month. No credit card.

Get Free API Key

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