Cloudflare cache responses

The CF-Cache-Status header output indicates whether a resource is cached or not. To investigate cache responses returned by this header, use services like Redbot , webpagetest.org , or a visual tool like Cloudflare Optics plugin .

Below you can find a comprehensive breakdown of Cloudflare's cache response statuses.

The resource was found in Cloudflare's cache.

The response is eligible for cache but was not present in Cloudflare's cache at request time, so it was served from the origin web server. Responses that Cloudflare chooses not to cache return BYPASS instead of MISS.

Cloudflare generated a response that denotes the asset is not eligible for caching. This may have happened because:

• A Worker generated a response without sending any subrequests. In this case, the response did not come from cache, so the cache status will be none/unknown.

• A Worker request made a subrequest (fetch). In this case, the subrequest will be logged with a cache status, while the main request will be logged with none/unknown status (the main request did not hit cache, since Workers sits in front of cache).

• A WAF custom rule was triggered to block a request. The response will come from the Cloudflare global network before it hits cache. Since there is no cache status, Cloudflare will log as none/unknown.

• A redirect rule or Always Use HTTPS caused the global network to respond with a redirect to another asset/URL. This redirect response happens before the request reaches cache, so the cache status is none/unknown.

The resource was found in Cloudflare's cache but was expired and served from the origin web server.

The resource was served from Cloudflare's cache but was expired. Cloudflare could not contact the origin web server to retrieve an updated resource.

Cloudflare considered the asset eligible for cache at request time either because it matches the default cached file extensions, or because a Cache Rule enabled caching for it but the origin response was ultimately not cacheable.

Common reasons the origin response is treated as not cacheable include:

• The response exceeds the maximum cacheable file size for your plan.
• The origin returned Cache-Control: no-store or private. These directives prevent caching in either Origin Cache Control mode.
• The origin returned Cache-Control: no-cache, max-age=0, or s-maxage=0, and Origin Cache Control is disabled (the default on Enterprise plans). With Origin Cache Control enabled (the default on Free, Pro, and Business plans), these directives cause Cloudflare to cache and revalidate the response instead, producing REVALIDATED or EXPIRED. Refer to Understand no-store and no-cache directives and the Conditions table.
• The origin returned a Set-Cookie header. Refer to Interaction of Set-Cookie response header with Cache for the specific configurations that produce BYPASS.
• The origin returned a Vary: * response header, which always bypasses cache.
• The request included an Authorization header and Origin Cache Control is enabled (the default on Free, Pro, and Business plans). In that mode, the response is cacheable only if Cache-Control also includes public, s-maxage, or must-revalidate. On Enterprise plans with Origin Cache Control disabled, Authorization does not by itself prevent caching.

BYPASS means the decision not to cache was made at response time the request was initially eligible for caching, but the origin response or response headers instructed Cloudflare not to cache. For example, a Cache Rule that sets "cache": true enables caching at request time, but if the origin returns Cache-Control: no-store, the response will be BYPASS.

If you expected a URL to be cached but see BYPASS, refer to Investigate uncached responses for a step-by-step diagnostic.

The origin confirmed the cached resource was unchanged via a conditional request (If-Modified-Since or If-None-Match), and the response is served from Cloudflare's cache. This status reflects the synchronous validation path the request waits for the origin to respond before being served.

With asynchronous stale-while-revalidate, most revalidations now return UPDATING or HIT instead. REVALIDATED is seen in the following situations: stale-while-revalidate is not set; or directives like must-revalidate or no-cache (with Origin Cache Control enabled) prevent stale content from being served.

The resource was expired but served from Cloudflare's cache while the origin updates it in the background. UPDATING is the expected status during asynchronous stale-while-revalidate revalidation all requests during the revalidation window receive UPDATING or HIT rather than waiting for the origin.

Cloudflare determined at request time that the asset is not eligible for cache, so the request went to the origin web server without a cache lookup.

This typically happens when:

• The requested asset is not one of the default cached file extensions (for example, HTML or JSON) and no rule instructs Cloudflare to cache it.
• A Cache Rule with the Bypass cache setting matches the request. The legacy Cache Level: Bypass option in Configuration Rules or Page Rules behaves the same way.
• Development Mode is enabled on the zone, which suspends cache for three hours.

Use Cache Rules to change what content Cloudflare caches. Once the request is treated as eligible for cache, the CF-Cache-Status header will reflect the response-time cache decision (HIT, MISS, EXPIRED, REVALIDATED, BYPASS, and so on) refer to BYPASS for the case where the origin response is ultimately not cacheable.

If you expected the request to be eligible for cache but see DYNAMIC, refer to Investigate uncached responses.