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AnalyticsConsent required

What is the _clsk Cookie?

Set by Microsoft Clarity (Microsoft Corporation). Expires after 1 day.

Purpose

Connects multiple page views by a user into a single Clarity session recording.

Cookie Details

Cookie Name_clsk
ServiceMicrosoft Clarity
ProviderMicrosoft Corporation
CategoryAnalytics
Duration1 day
Consent RequiredYes — requires explicit opt-in

Category: Analytics

Analytics cookies help website owners understand how visitors interact with websites by collecting and reporting information anonymously. Consent is required under GDPR.

GDPR Requirements

Under GDPR and the ePrivacy Directive, the _clsk cookie requires explicit user consent before it can be set. This means:

  • The cookie must not be set when a user first visits your site — not even for a fraction of a second
  • A consent banner must be displayed, and the user must actively accept analytics/marketing cookies
  • If the user rejects or ignores the banner, this cookie must remain blocked
  • The cookie must be listed in your cookie policy with its name, purpose, and retention period
  • Users must be able to withdraw consent at any time, which must also remove or invalidate this cookie

How to Handle This Cookie

  1. Block it by default — configure your Consent Management Platform (CMP) or tag manager to prevent Microsoft Clarity from loading until the user accepts analytics cookies.
  2. Include it in your consent categories — map it to the "Analytics" category in your CMP configuration.
  3. List it in your cookie policy — document the cookie name, purpose, provider (Microsoft Corporation), and expiry (1 day).
  4. Sign a DPA — ensure you have a Data Processing Agreement with Microsoft Corporation covering their use of data collected via this cookie.
  5. Verify it works — in an incognito browser, reject cookies and confirm _clsk is not set.

Other Microsoft Clarity Cookies

CookieCategoryDuration
_clckAnalytics1 year

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