Cookie List

Why does Clarity set cookies?

Clarity's normal functioning requires that we set cookies on your visitor's browser. These cookies are placed by the setup script that you installed to run Clarity. When the script is installed, Clarity's cookies send us nonpersonally identifiable information about your users.


  • If a user has disabled cookies on the browser, Clarity doesn't set cookies.

What cookies does Clarity set?

Name Purpose Value Passed
_clck Persists the Clarity User ID and preferences, unique to that site is attributed to the same user ID. String
_clsk Connects multiple page views by a user into a single Clarity session recording. String
CLID Identifies the first-time Clarity saw this user on any site using Clarity. String
ANONCHK Indicates whether MUID is transferred to ANID, a cookie used for advertising. Clarity doesn't use ANID and so this is always set to 0. Flag
MR Indicates whether to refresh MUID. Flag
MUID Identifies unique web browsers visiting Microsoft sites. These cookies are used for advertising, site analytics, and other operational purposes. GUID
SM Used in synchronizing the MUID across Microsoft domains. Character Flags

First-party and Third-party Cookies

First-party cookies: First-party cookies are created by websites that a user visit. It's used to save data related to user preferences and activities such as shopping cart items, sign in credentials.

Third-party cookies: Third-party cookies are placed by a domain other than the one the user explicitly visited. For example: like buttons and live chats.

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