Cookie Library · Essential
SID
A signed, encrypted record of your Google Account ID and last sign-in time. With HSID it is what keeps you signed in and blocks several kinds of attack.
- Owner
- Google LLC
- Matches
- The exact name
SID - Needed to Work
- Yes. Removing it can sign you out or break the site.
- Confidence
- Verified
- Source
- https://policies.google.com/technologies/cookies
- Last Reviewed
- 2026-09-15
Which Sites
Only on google.com and their subdomains. The same name on another site is a different cookie, and is not described here.