Cache behavior

In this page, we document how Cloudflare’s cache system behaves in interaction with HEAD requests and with Set-Cookie response header.

​​ Interaction of HEAD requests with Cache

Cloudflare converts HEAD requests to GET requests for cacheable requests.

When you make a HEAD request for a cacheable resource and Cloudflare does not have that resource in the edge cache, a cache miss happens. Cloudflare will send a GET request to your origin, cache the full response and return the response headers only. Make sure the origin server is setup to handle GET requests, even if only HEAD requests are expected, so that compatibility with this behavior is ensured.

​​ Interaction of Set-Cookie response header with Cache

For non-cacheable requests, Set-Cookie is always preserved. For cacheable requests, there are three possible behaviors:

• Set-Cookie is returned from origin and the default cache level is used. If origin cache control is not enabled, Cloudflare removes the Set-Cookie and caches the asset. If origin cache control is enabled, Cloudflare does not cache the asset and preserves the Set-Cookie.

• Set-Cookie is returned from origin and the cache level is set to Cache Everything. In this case, Cloudflare preserves the Set-Cookie but does not cache the asset. A cache MISS will be returned every time.

• Set-Cookie is returned from origin, the cache level is set to Cache Everything and edge cache TTL is set. In this case, Cloudflare removes the Set-Cookie and the asset is cached.

In this case, Cloudflare preserves the Set-Cookie but a cache MISS forever is returned, this means that the asset is not cached and MISS is returned every time.