SESKStuff Everyone Should Know
SESK: Stuff Everyone Should Know · sesk.info/tech-cache-control-no-cache

What does the HTTP header Cache-Control: no-cache actually mean?

You may store it, but must check with the server before reusing it.

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  1. Never store the response anywhere
  2. Store it, but revalidate with the server before reuse ✔
  3. Keep it forever

Why: Despite the name, no-cache does not stop caching. It forces the cache to ask the server whether its copy is still good. If you truly want nothing stored, the header is no-store.

Huh, didn't know that: Cache-Control: max-age=604800 means a stored copy stays fresh for one week, 604,800 seconds.

The dad joke
No-cache does not mean no cache. HTTP headers love a plot twist.
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References

Answer: Store it, but revalidate with the server before reuse. Despite the name, no-cache does not stop caching. It forces the cache to ask the server whether its copy is still good. If you truly want nothing stored, the header is no-store.

  1. MDN: HTTP caching developer.mozilla.org/en-US/docs/Web/HTTP/Guides/Caching
    The no-cache directive does not prevent the storing of responses but instead prevents the reuse of responses without revalidation.
    Checked 2026-10-10.

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