The MUID cookie is used by Microsoft for advertising and measurement. Below are the concise facts on who sets it, what it does, how long it lasts, and the consent type.
At a glance
Who sets it: Set by Microsoft for its Microsoft Advertising (Bing Ads) ad platform.
What it does: Identifies browsers for ad personalization, frequency capping, and measurement of ad performance.
Duration: Persists for about two years.
Consent type: Advertising/marketing cookie—treated as non-essential and typically requires user consent for tracking.
To view this cookie in your browser, see our guide: How to Inspect Cookies in Your Browser.
MUID supports targeted ads and analytics; manage it through your cookie preferences or ad privacy controls if you want to limit personalized advertising.