Cache-Control analyzer
Paste a Cache-Control response header to understand browser and CDN freshness, revalidation, and storage rules.
No signup. Inputs stay in your browser.What this header says
Browser freshness300 s
Shared-cache freshness3,600 s
Freshness values apply only when storage and reuse are allowed. no-store, private, no-cache, response age, and CDN rules can change the outcome.
public- Shared caches may store this response, subject to other directives and cache rules.
max-age=300- How long the response remains fresh in seconds.
s-maxage=3600- Freshness lifetime for shared caches; overrides max-age and Expires there.
stale-while-revalidate=60- Allows stale reuse for this many seconds while revalidation happens.
THE NEXT USEFUL STEP
Get my free cache report Check whether your public pages actually return cache hits.
Get a free account with three websites and 1,000 shared warming units per calendar month. Verify ownership, choose public pages, and review the results.
No card or CDN API key required.How to check a Cache-Control header
- Open a public page in your browser and find its response in the Network panel.
- Copy only the Cache-Control response header into the analyzer.
- Review storage restrictions and freshness values, then test the live page with the CDN cache inspector.
Does a public header prove a cache HIT?
No. This tool interprets the policy you paste. A confirmed HIT needs response evidence from the cache serving the request.