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⚡ Cache Header Analyzer

Analyze Cache-Control, ETag, Expires, Vary, Age — with human-readable max-age / s-maxage. Auto-detects major CDNs (Cloudflare, CloudFront, Fastly, Akamai, Vercel).

✅ 100% free, no signup

⚠️ Requests are made from DevLab servers. Private IP addresses and localhost are not allowed.

📚 Cache-Control Reference

• public: Cacheable by any cache including CDN/proxy

• private: Browser only (no shared caches)

• no-store: Never cache anywhere

• no-cache: May cache, but must revalidate every time

• max-age=N: Fresh for N seconds

• s-maxage=N: max-age applied only to shared caches (CDN)

• immutable: No revalidation even on reload — perfect for hashed assets

• stale-while-revalidate=N: Serve stale up to N seconds while revalidating in background

• stale-if-error=N: Serve stale up to N seconds on origin error

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