What is the datr cookie?
The datr cookie is set by Facebook (Meta) on the facebook.com domain, but it can also appear on third-party websites when they load Facebook elements such as the "Like" button, social sharing plugins, or the Facebook Pixel for conversion tracking.
It typically appears as soon as the page loads and a Facebook script runs in the browser, regardless of whether the visitor has a Facebook account.
What data it stores
Facebook publicly describes datr as being used to identify the browser used to access its services, mainly for security and platform-integrity purposes (detecting suspicious activity, fake accounts, and attacks). Its value is a unique identifier tied to the browser, generated by Facebook; the exact value format is not publicly documented and may vary.
Data collected through this cookie is sent to Facebook/Meta's servers, not to the hosting website.
What it is used for
For Facebook, datr helps identify browsers linked to fraudulent or abusive activity and helps protect users and the platform. Meta also associates it with measurement and ad-targeting functions within the Facebook Ads ecosystem.
For the site embedding a Facebook plugin, the cookie provides no direct benefit — it's simply a technical side effect of using those tools (Like button, Facebook Pixel, etc.).
Does it require consent?
In CookieFix's classification, datr falls under the marketing category (advertising/tracking), since it is placed by Facebook and can contribute to profiling and ad targeting.
- It requires the visitor's prior consent under Romania's Law 506/2004 (transposing the ePrivacy Directive) and the GDPR before being set.
- Site owners must disclose it explicitly in their cookie policy, listing the provider (Facebook/Meta) and its actual duration.
- Facebook remains a (co-)controller for the data collected through this cookie, per its own policies.
How to block or delete datr
A visitor can delete or block datr through browser cookie settings (per-domain management) or by using privacy/ad-blocking extensions.
For site owners, Facebook scripts (Like button, Pixel, social plugins) must be technically blocked until consent for the marketing category is obtained. A CMP platform like CookieFix can automatically prevent these Facebook scripts from loading until the visitor accepts marketing cookies, avoiding premature setting of the datr cookie.
Frequently asked questions
It's a cookie set by Facebook to identify the browser, officially used for security purposes but also playing a role in advertising within the Meta ecosystem.
Its typical duration is around 2 years, after which the browser removes it automatically unless renewed by a new Facebook script.
It's not strictly necessary for the hosting site to function; it's generated by embedded Facebook tools (Like, Pixel) and classified as marketing.
Yes, since it's a marketing cookie, it requires the visitor's prior consent under the GDPR and Law 506/2004, and the script that sets it must be blocked until acceptance.