What is the _clsk cookie?
Connects multiple Microsoft Clarity page views into a single recorded session.
Analytics Needs consent
| Cookie name | _clsk |
|---|---|
| Set by | Microsoft Clarity |
| Category | Analytics |
| Typical duration | 1 day |
| Domain | first-party |
| Consent required? | Yes — before it is set |
Does _clsk need consent?
Yes. _clsk is a analytics cookie, and under the EU ePrivacy rules (and the Irish ePrivacy Regulations) a site must get your prior, informed consent before setting it. If you see _clsk on a site before you click "Accept" on a cookie banner — or on a site with no banner at all — that is very likely a compliance problem.
Is _clsk a tracking cookie?
Measures how visitors use the site. Requires consent first — "anonymous" or first-party does not exempt it.
In practice that means Microsoft Clarity can recognise your browser so the site owner can measure how you and others use the site. It is not malware and it cannot read files on your device — but it is exactly the kind of cookie consent law is designed to cover.
How to see and remove _clsk
- See it: open your browser's developer tools → Application (Chrome/Edge) or Storage (Firefox) → Cookies, and look for
_clsk. - Remove it: clear cookies for the site, or use your browser's "Clear browsing data" for cookies. It will reappear if you keep using the site and consent is in place.
- Stop it being set: decline non-essential cookies on the site's banner. On a compliant site, clicking "Reject all" prevents _clsk from being set at all.
Want to know which cookies your site sets — and whether any fire before consent? Scan it free and get the full list, categorised, with the ones that load too early flagged.
Fixing pre-consent cookies
If a scan shows _clsk or other tracking cookies loading before the visitor consents, the fix is a consent management platform (CMP) that blocks non-essential tags until the visitor agrees. Cookies.ie is our GDPR / ePrivacy CMP — EU-hosted, with a real one-click "Reject all" and consent logging. See the fix guide for pre-consent trackers.
Related cookies
_clck— Microsoft Clarity_ga— Google Analytics_ga_<container-id>— Google Analytics 4_gid— Google Analytics
Cookie purposes and durations reflect vendor documentation and common consent databases as of 2026-06-25; a specific site may configure _clsk differently. This is general information, not legal advice.