Speed · SSL · SEO · Security · Performance

DNS & CDN

This check lists nameservers, CNAME targets and cache headers. Cloudflare and other CDNs often show up as NS, CNAME or headers such as cf-ray.

Frequently asked questions

Does Cloudflare always mean a CDN?
Cloudflare can be DNS-only (grey cloud) or proxy (orange cloud). A cf-ray header means the HTTP hop went through their proxy.
What is a good Cache-Control?
HTML is often private or short-lived. Static files should have a long max-age plus a fingerprint in the URL.