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Microsoft Clarity


Microsoft Clarity

Clarity is a user behaviour analytics tool that helps you understand how users interact with your website. Supported features include:

  • Session Recordings
  • Heatmaps (or heat maps)
  • ML Insights

Clarity retains data differently. Recordings data is retained for 30 days. Any labelled or favourited sessions are retained for 13 months. Heatmaps data is retained for 13 months. You can opt out of cookiesView Microsofts privacy policy for more information.

Cookie Purpose Value Passed Expiration
_clck Persists the Clarity User ID and preferences, unique to that site is attributed to the same user ID. String 13 months
_clsk Connects multiple page views by a user into a single Clarity session recording. String 30 days
CLID Identifies the first-time Clarity saw this user on any site using Clarity. String 13 months
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 13 months
MR Indicates whether to refresh MUID. Flag 13 months
MUID Identifies unique web browsers visiting Microsoft sites. These cookies are used for advertising, site analytics, and other operational purposes. GUID 13 months
SM Used in synchronizing the MUID across Microsoft domains. Character Flags 13 months