What is the cf_ob_info cookie?
cf_ob_info is an HTTP cookie set by Cloudflare's edge infrastructure (not by a script loaded on the page) on any site using Cloudflare's proxy/CDN with network-level routing features. It typically appears alongside the cf_use_ob cookie, when Cloudflare needs to temporarily route requests to an alternative origin server, for instance when the primary origin is unavailable or times out.
Because the cookie is set by Cloudflare's edge server rather than by the site's JavaScript, it can appear even before a visitor has interacted with the consent banner.
What data it stores
The stored value is internal technical information Cloudflare uses to keep track of which origin server the current request should be routed to. Its exact field structure is not documented publicly, and it does not contain directly identifying personal data such as a name, email, or explicit IP address.
The cookie is read only by Cloudflare's network (edge servers and routing infrastructure), not by the site itself or by marketing third parties.
What it is used for
The cookie's purpose is purely operational: it helps Cloudflare maintain a consistent connection for the visitor when there are temporary issues with the site's origin server, so subsequent requests in the same short session are sent to the correct server. It is not used for measurement, advertising, or user profiling.
Does it require consent?
In CookieFix's classification, cf_ob_info is marked as strictly necessary. Under the ePrivacy Directive (2002/58/EC), transposed in Romania via Law 506/2004, and GDPR (Regulation 2016/679), cookies indispensable to the technical delivery of a service explicitly requested by the user do not require prior consent.
- The site owner does not need to request opt-in for this cookie.
- It should still be listed in the cookie policy, with provider (Cloudflare), category (necessary), and duration.
- If the site also uses other Cloudflare cookies for analytics or marketing, those need separate assessment, as they may require consent.
How to block or delete cf_ob_info
A visitor can delete or block cf_ob_info through the browser's cookie settings (per-site cookie management) or by browsing in private mode. Since it is set directly by Cloudflare's network-level proxy rather than a page script, blocking it in the browser could, in rare cases, affect correct routing during an origin connectivity issue, without otherwise disrupting normal browsing.
For site owners: as a strictly necessary cookie set by Cloudflare's infrastructure (not by a JS script on the site), consent management platforms like CookieFix do not block it before consent, since there is no page script to delay — CookieFix detects it automatically during a scan and documents it in the cookie policy, while still blocking non-essential Cloudflare scripts (such as analytics) until the visitor gives consent.
Frequently asked questions
No. It's a technical cookie Cloudflare uses to route requests to the origin server, not for advertising or behavioral analytics.
It has a very short lifespan, around one minute, after which it expires automatically.
No, since it's strictly necessary for the site's technical operation, but it should still be listed in the cookie policy.
Generally nothing noticeable, but in rare cases of origin server issues, Cloudflare's fallback routing may be less effective.