The TikTok Pixel, and the pixels beside it
The TikTok Pixel is a snippet an advertiser puts on their own website so that TikTok can connect what happens there — a signup, a purchase, a page view — back to an ad someone was shown. It is catalogued here under advertising and classified as tracking, which makes it one of the more clear-cut entries in the index: nobody installs it by accident. It was found on 62 of the 5,294 sites measured, 1.2% of them. The interesting thing about those 62 sites is that a site running one advertising pixel almost never runs only one.
Pixels arrive in sets
On the 62 sites carrying the TikTok Pixel, a second TikTok hostname, tiktokw.us, was present on 43 (69.4%). Google was on 54 (87.1%). Then the other networks: Meta Pixel on 25 (40.3%), Meta on 24 (38.7%), LinkedIn on 15 (24.2%), X on 11 (17.7%), Microsoft Ads on 10 (16.1%) and Snap Pixel on 8 (12.9%). OneTrust and Cloudflare complete the ten, on 9 and 8 sites.
Six separate advertising platforms in one co-presence list is the finding. The decision a marketing team makes is not "should we add TikTok" but "which networks are we buying on this quarter", and each answer leaves its own snippet in the page. The median site here had 4 companies classified as tracking, 19th of the 88 in this index, and that number is mostly this list.
These pages fill in late
The median time to first third-party contact on these sites was 956 ms, sixth-highest of the 88 companies profiled here. 52 of the 62 sites recorded early contact, 83.9%, which ranks 84th of 88 — close to the bottom of the table. And on the median site, 4 companies arrived after the consent window had closed.
A page carrying four catalogued trackers that still reaches nobody in its opening moments is an unusual shape. alphapolis.co.jp is the clearest case: 12 companies over the whole page, none of them inside the early window, first contact at 2,642 ms. suumo.jp did the same with 10 and 0.
And some of them do not
The other half of the sample is the opposite shape. nubank.com.br contacted 14 companies with all 14 inside the early window and a first contact at 162 ms, the fastest recorded anywhere in this group. curseforge.com contacted 13 with all 13 inside it. cursor.sh contacted 11 with all 11 inside it. heylink.me contacted 11, all inside, at 400 ms.
A median of 956 ms sitting on top of that spread means the group holds two populations rather than one typical page. Five of the twelve sampled sites had every company, or all but one, inside the window; four had at most one.
Where it was found
The sample is geographically spread: Brazil (nubank.com.br, olx.com.br), Japan (suumo.jp, alphapolis.co.jp), two American public universities (ucsd.edu, colorado.edu), streaming and games (kick.com, curseforge.com), sport (mlb.com), a developer tool (cursor.sh), a link-in-bio service (heylink.me) and a podcast host (anchor.fm).
Universities are worth pausing on: ucsd.edu and colorado.edu are both in the list, with 9 and 12 companies respectively and neither showing a detectable consent tool. A recruitment campaign on a social network is a normal thing for a university to run, and this is what it leaves behind on the site.
Consent tools on those pages
18 of the 62 sites carried a consent tool the crawl could detect: OneTrust seen alongside on 9, an IAB TCF banner on 8 and Cookiebot on 1.
Under a third, on a set of pages defined by carrying an advertising pixel. In the sample, kick.com, mlb.com, heylink.me and anchor.fm ran OneTrust and olx.com.br a TCF banner; the other seven showed nothing detectable. By site count the TikTok Pixel is 67th of the 88 companies here, so this is a small footprint — but a very consistent one.
| Site | Companies | Before consent | First contact |
|---|---|---|---|
| kick.com | 10 | 3 | 1483 ms |
| cursor.sh | 11 | 11 | 834 ms |
| mlb.com | 13 | 1 | 1437 ms |
| heylink.me | 11 | 11 | 400 ms |
| curseforge.com | 13 | 13 | 226 ms |
| olx.com.br | 13 | 9 | 949 ms |
| suumo.jp | 10 | 0 | 2162 ms |
| alphapolis.co.jp | 12 | 0 | 2642 ms |
| ucsd.edu | 9 | 1 | 686 ms |
| nubank.com.br | 14 | 14 | 162 ms |
| colorado.edu | 12 | 9 | 445 ms |
| anchor.fm | 7 | 6 | 424 ms |
| Tool | Sites |
|---|---|
| OneTrust | 9 |
| IAB TCF consent tool | 8 |
| Cookiebot | 1 |
Seen on the same pages
Companies most often contacted by the same sites. Co-presence only — the crawl records what arrived, not who called whom.
- GoogleTogether on 54 of these sites
- Meta PixelTogether on 25 of these sites
- MetaTogether on 24 of these sites
- LinkedInTogether on 15 of these sites
- XTogether on 11 of these sites
- Microsoft AdsTogether on 10 of these sites
- OneTrustTogether on 9 of these sites
- CloudflareTogether on 8 of these sites
Questions
What does the TikTok Pixel do?
It reports actions on an advertiser's own website back to TikTok so that ad spend can be matched to outcomes. It is catalogued in this index under advertising and classified as tracking.
How often does it appear on its own?
Rarely. A second TikTok hostname was on 43 of the 62 sites, Google on 54, Meta Pixel on 25, LinkedIn on 15, X on 11, Microsoft Ads on 10 and Snap Pixel on 8.
How many of these sites had a consent tool?
18 of 62. OneTrust was seen on 9, an IAB TCF banner on 8 and Cookiebot on 1.
Is 62 sites a large footprint?
No — 1.2% of the 5,294 sites measured, and 67th of the 88 companies profiled in this index by site count.
Why is the first contact so late on these pages?
The median is 956 ms, sixth-highest of the 88 companies here, but the group splits: several sampled sites contacted nobody inside the early window at all, while others had every company inside it and were done inside the first second.