PHPSESSID is a session identifier used by sites built on PHP. Below are the key facts: who sets it, its purpose, duration, and consent status.
Who sets it
The PHP Group / PHP session module — created by web servers running PHP (common in CMSs and custom PHP apps).
What it does
Holds a session ID that links the browser to server-side session data (login state, cart contents, short-term preferences).
Duration
Typically a session cookie that expires when the browser closes, unless the site explicitly makes it persistent.
Consent type
Classified as strictly necessary/essential for site functionality, so explicit consent is generally not required for basic operation.
Inspect this cookie
See the cookie in your browser using the built-in developer tools — instructions at How to inspect cookies in your browser.
If you want to see which sites set PHPSESSID or other trackers, check our post: How To See Who's Tracking You.