Check what tracking a page is running — Google Analytics 4, Google Tag Manager, Meta Pixel, LinkedIn, Microsoft Clarity, Hotjar, TikTok and more — with the IDs where we can read them. Confirm your own setup, or see what a competitor uses.
⚡ Interactive demo — sample data
4 analytics/tracking tools detected on this sample page — including a leftover Universal Analytics tag to remove.
Google Analytics 4 — Detected (G-AB12CD34EF)Looks good
Google Tag Manager — Detected (GTM-XYZ123) — other tags may load through this containerLooks good
Meta Pixel (Facebook) — Detected (ID 198273645012345)Looks good
Universal Analytics (legacy) — Detected (UA-12345678-1) — sunset July 2023, safe to removeWarning
Note: tags loaded only after cookie consent or injected by JavaScript may not appear in the raw HTMLWarning
Check what tracking a page is running — Google Analytics 4, Google Tag Manager, Meta Pixel, LinkedIn, Microsoft Clarity, Hotjar, TikTok and more — with the IDs where we can read them. Confirm your own setup, or see what a competitor uses.
How it works
Enter any page URL
Paste the URL of a page you want to inspect — your own or a competitor's — and run the check. We fetch the page's HTML and scan it for the script snippets, network calls, and ID patterns that analytics and ad-tracking tags leave behind.
See what's installed
You get a list of every detected tool — Google Analytics 4, Tag Manager, Meta Pixel, LinkedIn Insight, Microsoft Clarity, Hotjar and more — with the tracking ID where it's readable in the page (for example a G-XXXXXXXXXX or GTM- container). A count of total tags found sits at the top.
Confirm or compare
Use the result to verify your own setup is firing the right tags, or to see what a competitor runs. Re-run after changes to confirm a tag was added or removed. Remember the caveat below: tags that load only after consent or are injected later by JavaScript may not show in the raw HTML.
What we check
Google Analytics 4 — Detects GA4 via the gtag() call, the googletagmanager.com/gtag/js loader, or a measurement ID in the G-XXXXXXXXXX format. When the ID is present in the HTML, we surface it so you can confirm it's the right property.
Universal Analytics & Google Tag Manager — Flags legacy Universal Analytics (UA-XXXXXXXXX-X), which Google sunset in July 2023 and should no longer be collecting data, and Google Tag Manager (GTM- containers), which often loads other tags through it.
Google Ads conversion tracking — Detects Google Ads tags via the AW- conversion ID or the googleadservices.com call — the signal that a page is wired for paid-search conversion and remarketing.
Meta, LinkedIn, TikTok, Pinterest & X pixels — Identifies the major social and ad pixels: Meta/Facebook Pixel (with its numeric ID where readable), LinkedIn Insight Tag, TikTok Pixel, Pinterest Tag and the X/Twitter Pixel — the tags that power retargeting audiences.
Behavior & session tools — Catches Microsoft Clarity and Hotjar — heatmap and session-recording tools — which collect very different data from analytics counters and are worth knowing about for both setup and privacy review.
Microsoft/Bing UET & HubSpot — Detects the Microsoft Advertising (Bing) UET tag and HubSpot's tracking script, covering Microsoft's ad conversion tracking and HubSpot marketing analytics.
Tracking IDs where readable — For tags that expose an identifier in the page source — GA4, Tag Manager, Google Ads and Meta Pixel — we extract and show it. Others (Clarity, Hotjar, LinkedIn) load their ID indirectly, so we confirm the tag without always showing a number.
Common issues we catch
A tag fires through Tag Manager but doesn't show individually — Google Tag Manager loads other tags at runtime, so if a page uses GTM you may see only the GTM container here even though GA4, a Meta Pixel and others fire through it. Detecting GTM is a hint that more tags exist than the raw HTML reveals.
Tags that load only after cookie consent — Sites in the EU and elsewhere often hold tracking tags until a visitor accepts the cookie banner. Those tags aren't in the initial HTML we fetch, so a page can show as 'no tags' here yet track every consenting visitor. Always confirm with consent given.
JavaScript-injected tags — Some tags are added to the page by client-side JavaScript after load rather than written into the source. If a tool detects nothing but you know analytics is running, it's likely injected at runtime — check in your browser's network tab with the page fully loaded.
Stale Universal Analytics still on the page — Universal Analytics stopped processing data in July 2023, but the old UA- snippet is often left in templates long after. Finding it here means dead code to remove, not data you're still collecting.
Duplicate or double-firing tags — A measurement ID hard-coded in the page and also added through Tag Manager can double-count traffic and conversions. If you spot the same product detected through two paths, your numbers may be inflated.
A tag on staging or the wrong property ID — Reading the actual ID matters: a page may carry a tag but point at a test property, a dev container, or another brand's ID copied during a template build. Seeing the real G- or GTM- value is how you catch that.
Tags hidden behind a tag-management or server-side setup — Server-side tagging and first-party proxying route tracking through the site's own domain instead of the usual vendor scripts. Those calls won't match standard signatures, so a privacy-forward or advanced setup can read as cleaner than it is.
Where this matters
Google Analytics 4 & Universal Analytics — We detect current GA4 (G-XXXXXXXXXX) and the retired Universal Analytics (UA-XXXXXXXXX-X) separately, so you can tell live measurement from leftover legacy code.
Google Tag Manager & Google Ads — Covers the GTM- container and the AW- Google Ads conversion tag — the two pieces most paid-marketing setups depend on.
Meta, LinkedIn, TikTok, Pinterest & X — The major advertising pixels used for retargeting and conversion tracking across the big social and ad platforms, with IDs where they're readable in the page.
Microsoft Clarity, Hotjar & Bing UET — Session-recording and heatmap tools (Clarity, Hotjar) plus Microsoft Advertising's UET conversion tag — useful for both setup checks and privacy reviews.
HubSpot & marketing analytics — Detects the HubSpot tracking script, common on B2B and marketing-led sites that tie page activity to CRM contacts.
Frequently asked questions
How does the tracking detector find tags?
It fetches the page's HTML and looks for the script snippets, vendor network calls, and ID patterns that each tool leaves in the source — for example the gtag() call for Google Analytics 4 or the fbq() call for the Meta Pixel. When a readable ID is present, it shows that too. It does not run the page as a full browser.
Why does a page I know has analytics show no tags?
The two usual reasons are cookie consent and JavaScript injection. Many sites hold their tracking tags until a visitor accepts the cookie banner, and some add tags at runtime via JavaScript — in both cases the tags aren't in the raw HTML we read. Check again with consent given, using your browser's network tab on the fully loaded page.
Can I use this to see what a competitor uses?
Yes. Because the tags are in the public page source, you can run any URL and see which analytics and ad platforms it's set up on. It's a quick way to learn whether a competitor is running paid social, remarketing, or session recording — though the consent and JavaScript caveats apply to their site too.
Why do some tools show an ID and others don't?
Tools like Google Analytics 4, Tag Manager, Google Ads and the Meta Pixel write a readable identifier into the page, so we extract and show it. Others — Clarity, Hotjar, LinkedIn — load their ID indirectly, so we confirm the tag is present without always showing a number.
I only see Google Tag Manager — does that mean nothing else is tracking?
No. Tag Manager is a container that loads other tags at runtime, so GA4, a Meta Pixel, and others can all fire through it without appearing individually in the HTML. Finding GTM is a strong hint that more tracking exists than the raw source shows.
Does finding Universal Analytics mean it's still collecting data?
No. Google sunset Universal Analytics in July 2023, so the old UA- property no longer processes hits. Seeing the snippet here almost always means leftover code in your template that you can safely remove — and you should be on Google Analytics 4 instead.
Is detecting these tags a privacy concern?
The tool only reads tags already published in a page's public source — it doesn't collect anything about visitors. That said, the list is useful for your own privacy review: it shows which third-party trackers a page loads, which matters for consent banners and privacy-policy disclosures.
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