What is the ajs_anonymous_id cookie?
Assigns an anonymous ID so Segment can attribute events to a visitor before they are identified.
Analytics Needs consent
| Cookie name | ajs_anonymous_id |
|---|---|
| Set by | Segment |
| Category | Analytics |
| Typical duration | 1 year |
| Domain | first-party |
| Consent required? | Yes — before it is set |
Does ajs_anonymous_id need consent?
Yes. ajs_anonymous_id 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 ajs_anonymous_id 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 ajs_anonymous_id a tracking cookie?
Measures how visitors use the site. Requires consent first — "anonymous" or first-party does not exempt it.
In practice that means Segment 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 ajs_anonymous_id
- See it: open your browser's developer tools → Application (Chrome/Edge) or Storage (Firefox) → Cookies, and look for
ajs_anonymous_id. - 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 ajs_anonymous_id 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 ajs_anonymous_id 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
_ga— Google Analytics_ga_<container-id>— Google Analytics 4_gid— Google Analytics_gat— Google Analytics
Cookie purposes and durations reflect vendor documentation and common consent databases as of 2026-06-25; a specific site may configure ajs_anonymous_id differently. This is general information, not legal advice.