Website Tracking IDs: GA4, GTM, Google Ads, Meta Pixel and more

Give it websites, get back the actual tracking IDs each one runs: Google Analytics 4 (G-…), Universal Analytics, Google Tag Manager (GTM-…), Google Ads (AW-…), Floodlight, Meta Pixel, LinkedIn Insight, Microsoft Ads UET, X, Reddit, Snap, Clarity, Hotjar and others. Plain HTTP by default (cheap and fast); an optional browser mode finds the tags that JavaScript adds after the page loads. No proxy, no login.

What makes it different from a tech-stack detector: most big sites load GA4, Google Ads and ad pixels through Google Tag Manager, so the page HTML shows only GTM-XXXX. This actor opens that public GTM container, reads it as data (not as text), and returns the IDs of the live tags inside it. Paused tags are skipped, and constant GTM variables are filled in. On allbirds.com the page HTML alone shows 2 tools (Clarity, GTM); with the container read it shows 8, including 9 GA4 IDs, 2 Google Ads IDs and a TikTok Pixel ID.

Who uses it

• Ad and analytics agencies auditing a client's or a competitor's tracking setup, or checking that a pixel is on the site.
• Lead-gen and sales teams qualifying companies by what they run (a Meta Pixel or Google Ads ID means they buy ads).
• Researchers and OSINT linking sites that share one analytics or ad account.

Input

{"urls": ["hubspot.com", "https://www.allbirds.com"], "readGtmContainers": true, "browser": "off"}

Field	Meaning
urls	Domains or URLs, one per line.
readGtmContainers	Read the GTM containers found on the page (default on).
browser	off (default): plain HTTP. fallback: pages that return no ID, or refuse the plain request (403/429), are opened again in Chromium. always: every page is opened in Chromium.
concurrency	Sites fetched in parallel, default 5.
maxUrls	Stop after this many sites.

Output (one row per website)

{
  "url": "https://hubspot.com/",
  "ok": true,
  "ids": {"ga4": ["G-LXTM6CQ0XK"], "gtm": ["GTM-N5LT88"], "meta_pixel": ["893596480692132"]},
  "technologies": [{"name": "Google Analytics 4", "kind": "analytics", "ids": ["G-LXTM6CQ0XK"], "sources": ["gtm:GTM-N5LT88"]}],
  "gtmContainers": [{"container": "GTM-N5LT88", "fetched": true, "liveTags": 385, "pausedTags": 6}]
}

sources says where each ID was found: page, gtm:GTM-…, and in browser mode also page (rendered) and network request. (The example shows three of the ID types the row holds.)

Shared IDs across your list

When you give several sites, the run ends with one extra free row ("type": "sharedIds") listing the analytics, ad, tag-manager and CRM IDs that appear on more than one of them, which points to the same owner or agency. Test on 126 real sites: one shared ID, the GA4 ID G-C3QZPB4GVE on theverge.com and vox.com (found in both pages' HTML). Most unrelated companies share nothing, so expect an empty result on a random list.

What the tests showed

Run on 136 test rows (real company sites, 95 fetched, 41 blocked or failed): 62 sites returned at least one ID. Of the sites that had a GTM container, all 38 containers were read. Every one of the 562 IDs returned was checked to exist as text in the page or container it came from (562 of 562). Every tool in the table came back with a non-empty ID each time it was detected, except where noted:

Tool	Sites detected	With an ID
Google Tag Manager	37	37
Google Analytics 4	34	34
Google Ads (live tags)	33	33
Google Ads (accounts linked in container settings)	24	24
Meta (Facebook) Pixel	23	23
LinkedIn Insight Tag	20	20
Universal Analytics	20	20
Microsoft Advertising UET	25	22
TikTok Pixel	10	10
Hotjar	4	4

Most sites simply do not run a TikTok pixel or Hotjar, so those are rarer in the results. Consent tools (OneTrust: 7 detected, 4 with an ID) are often detected by script name only. "Linked in container settings" are Google Ads accounts the container is connected to; they are listed separately from live conversion tags.

Compared with other Store actors

Same 20 sites (asana.com, monday.com, salesforce.com, wired.com and 16 more) run through this actor and three actors that return tracking IDs, on 2026-10-04. IDs returned in total / sites with at least one ID. Prices are the current ones from each actor's Store record, checked against what our runs of them were charged:

Actor	Price	IDs	Sites
This actor, browser: off	$0.002 per website	229	20
This actor, browser: always	$0.008 per website rendered	324	20
smart-digital/website-tags-pixels-detector (real browser)	$0.01 per result	59	19
trovevault/ad-pixel-id-extractor	$0.002 per website + $0.001 per start	66	6
memo23/tiktok-kwai-ads-checker	$0.004 per company + $0.005 per start	53	15

With browser: off the price equals trovevault's; the difference is the output. Meta Pixel IDs: this actor 21 IDs on 11 sites; trovevault 5 on 3; memo23 0. LinkedIn: 24 IDs on 9 sites against 1 on 1 (trovevault). Microsoft Ads UET: 9 sites against 0. Where the others found more: smart-digital runs a real browser; on gitlab.com, glossier.com, gymshark.com, klaviyo.com, monday.com and ycombinator.com it returned 16 IDs that the plain mode did not. With browser: always this actor returned 14 of those 16 (the 2 it did not return are GA4 IDs on klaviyo.com; our server was redirected to klaviyo.com/de/, where the page carries a different GA4 ID, so these 2 depend on the visitor's country). trovevault returned 21 "Google Ads" IDs (AW-…) on salesforce.com, klaviyo.com and techcrunch.com that this actor does not return; in the sites' containers all 21 are LinkedIn conversion IDs (tags carrying a LinkedIn partner ID), not Google Ads accounts. A second sample of 14 other sites gave the same picture for plain mode: Meta Pixel on 5 sites against 3, LinkedIn on 4 against 0, Microsoft Ads UET on 3 against 0 (this actor against trovevault). Both samples are sites where this actor found at least one ID.

Browser mode

Many sites add their tags with JavaScript, so the HTML the server sends shows few of them. browser: always opens each page in Chromium, waits 4 seconds, and reads the rendered page, the requests it made and the GTM containers it loaded. On the 20 comparison sites it returned 324 IDs against 229 in plain mode, and every ID the plain run had was still there. A page that returns IDs in the browser is charged as "Website rendered in a browser" ($0.008); in fallback mode only pages the plain request could not read, and pages that loaded but showed no ID, are opened this way. Second test, 41 big consumer and SaaS sites, browser: always: on the 35 sites that plain mode could fetch, 265 IDs in plain mode and 375 in browser mode, none lost; of the 6 sites that refused the plain request, 2 opened in the browser (canva.com, theguardian.com). Test on 30 sites not used before, browser: fallback: 26 fetched, 22 of them with IDs. Of 8 pages with no IDs in plain mode, the browser found IDs on 4 (trello.com 1, getresponse.com 16, brevo.com 7, gorgias.com 15) and nothing on 4. Of 3 pages that refused the plain request (403) in this set, the browser was refused too.

Second test on 40 more sites not used before (mostly US retail, ticketing and pet/outdoor stores): plain mode fetched 23 and returned 120 IDs on 13 of them (120 of 120 found as text in their page or container); browser: fallback fetched 25, returned 204 IDs on 21, and was refused again by the 403 sites (sephora, doordash, ticketmaster, stubhub, seatgeek, sportsmans, cabelas, basspro, petco). Large retail sites often block automated requests: those rows are free. Limits: it took 1 min 21 s for 20 pages with 3 browsers in parallel (2 min 25 s with one); sites that show tags only after a cookie-consent click (shopify.com, notion.so in our test) still return nothing; sites that block Chromium (lego.com, salesforce.com's browser pass) return 403 and the plain result is kept. Memory is set from your input: 512 MB with browser: off; with browser mode 4 GB for 2-3 parallel Chromium browsers (measured peak 1.7 GB with 3) or 2 GB with browserConcurrency: 1 (measured peak 1.2 GB). You can still change it in the run options.

Price

$0.002 per website analyzed (plain HTTP). $0.008 per website rendered in a browser (only when browser is fallback or always and the browser run returned IDs). A website counts when its page was fetched (HTTP below 400). Sites that fail, block the request (403/429) or are not valid URLs are free.

Limits

• With browser: off (default) it reads the HTML the server sends, without running JavaScript. A site that injects its tags only after the page loads (single-page apps) may show few or no IDs; use browser: fallback or always for those.
• Some sites block automated requests: 24 of 82 big consumer sites in two tests (test sets 5 and 6) returned 403 or 429. Those rows say so and are not charged.
• Only the start page of each URL is read. Sites that serve other tags by country show the ones for the server's country (Germany in our tests).
• An ID in a GTM container belongs to a live tag, but the tag may fire only on some pages or after consent; this actor does not evaluate triggers. An ID the container builds from a runtime variable (for example a Meta Pixel ID taken from the data layer) cannot be read.