How to Find Which Companies on an Email List Run Tracking Tags
To find which companies on an email list run tracking tags, read the home page source of each address's domain and look for analytics, advertising and heatmap scripts. The bulk email website tracking detector does that for every address in a pasted list or CSV and gives each a row: Tracking tags seen, with the tag names, or No tracking tags seen.
A tag shows a service is installed, not that a campaign runs, and the check reads the domain, not the mailbox.
If you have a list of company websites rather than email addresses, see how to check which prospects run Google Analytics or Meta Pixel.
What the tags are good for on a list
Nobody installs the Google tag (how Google describes it) on a site they have forgotten. So a tag is a weak sign that a company maintains its site and measures it. On a long prospect list that is a way to put the maintained, measured company sites ahead of the neglected ones. It is not a measure of size or ad spend.
The by-hand way
- Take the domain after the @, for example
acme.example. - Open its home page and view the source.
- Search for
<script>elements and look at where they load from. MDN's page on the script element explains what you are reading. - Note the analytics, ad or heatmap services you recognise.
That is slow even for a dozen companies, and the list grows with every export.
Step 1: paste the addresses
Paste addresses one per line, or upload a CSV. Only the unique domains are sent, never the mailbox names, 10 a request.
Step 2: run the check
Press Detect tracking tags. Each home page is requested once from our server, with no cookies and nothing stored. No mail is sent.
Step 3: read the result
| Result | What it means |
|---|---|
| Tracking tags seen | One or more known tags are in the page source; the row names them |
| No tracking tags seen | None of the known tags was found |
| Answered 403 (or another status) | The page could not be read, so no verdict |
The CSV has the tag names and the final URL beside each address.
What this check cannot do
- It checks the domain, not the mailbox.
- Tags added through a tag manager or after a cookie banner load later and are not seen, so No tracking tags seen is not proof there are none.
- A tag is not proof of a running campaign.
- Only the home page is read, once per domain. Up to 100 unique domains a run without an account, 500 signed in. Free providers such as gmail.com are read like any other domain, so you get the provider's own site.
For the same read on bare domains, use the bulk website tracking detector. To see whether the company's site is up at all, use the bulk email website status checker, and see the lead-list quality check for where this fits.
Next: the mailboxes
A company with tags can still have closed any one address. Use the verify page on the list: the first 100 checks are free with a Google sign-in, no card.
Try it now
Paste your list into the bulk email website tracking detector.
Common questions
How do I find which companies on an email list run tracking tags?
Open each domain's home page source and look for analytics, advertising or heatmap scripts. A bulk email website tracking detector reads the home page of every address's domain and names the tags it sees.
Does a tracking tag mean the company is advertising?
No. A tag shows a service is installed, not that a campaign is running.
Why does a busy site show No tracking tags seen?
Its tags may load through a tag manager or after a cookie banner is accepted. The tool reads the page source as sent and does not run scripts.
What does Answered 403 mean?
The home page answered with a 403, so nothing was read. Some servers refuse requests that are not from a browser.
Does the check tell me whether the mailbox exists?
No. It checks the domain, not the mailbox.
Check your list before you send
Real mailbox checks over SMTP, and nothing is sent to the address. Sign in with Google and your first 100 email checks are free, no card. Plans for bigger lists are on the pricing page.