Find websites that share a Google Analytics ID

Published October 20, 2025 · Analytics · OSINT · 2 min read

Search the literal measurement ID — G-ABCDE12345 (GA4) or UA-123456-7 (legacy) — to surface every site sending data to that one property. Shared IDs are one of the oldest tricks in domain-attribution OSINT.

An Analytics property ID is meant to be unique to one owner, but people reuse it — across a main site and its landing pages, a portfolio of affiliate domains, or a network someone would rather keep separate. Because the ID is printed verbatim in the page source, one string ties the whole set together.

GA4 vs Universal Analytics

Modern sites load GA4 with a G- measurement ID; the footprint gtag/js?id=G- is on 7,800,085 sites (see the GA4 page). Legacy properties use a UA- ID — Universal Analytics's analytics.js is still on 3,554,799 sites even though Google stopped collecting UA data in 2023, which makes a stale UA ID a great fingerprint for older networks.

Pivot on a specific ID

Start from one known site, open its source, and copy its exact ID. Then search the literal string, e.g. "G-ABCDE12345". Every result is a page reporting to that same property. To sweep for all legacy IDs in a market rather than one, go regex: /UA-[0-9]{4,}-[0-9]/ matches the UA ID shape anywhere in source.

Read the source before you conclude

A shared ID is strong evidence, not proof — an ID can leak into a copied template, and agencies sometimes reuse one across unrelated clients. Open each result's full source and check the ID sits in the site's own tag, not a third-party embed. Then export the domain set and pivot again on anything else the pages share: an ad pixel, a support widget, a CDN account.

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Frequently asked questions

Can I find every site sharing one specific ID?

Yes — search the ID as a literal string (in quotes). Each result is a page that prints that exact measurement ID in its source.

GA4 or Universal Analytics?

GA4 IDs start with G- and load via gtag/js?id=G-. Universal Analytics IDs start with UA- and are still present on millions of un-migrated sites, which makes them useful for finding older networks.

Is a shared ID proof of common ownership?

It's strong evidence, not proof. IDs can be copied with a template or reused by an agency. Read each result's source to confirm the ID belongs to the site's own tag before drawing conclusions.