Companies Using Rezync (Zeta Global)

Most people who search for Rezync have just seen live.rezync.com in a blocker or a cookie list. The answer is simple: rezync.com is the domain of the Zync pixel, the container tag Zeta Global's clients put on their sites, according to Zeta's own tag and cookie documentation. Our October 2026 crawl finds a working Zync pixel on 1,631 domains, and we matched 942 of them to a company. Before writing I read the Zeta account name in every pixel we could see and asked Zeta's own endpoint whether each one still works.

What we took out, and why

Every Zync call carries a pixel ID and the name of the Zeta account that owns it, and the sync address answers differently for a live pixel and a dead one. A live pixel gets back its tag code. An unknown one gets an HTTP 400 that reads "Invalid partner". I could read the pixel on 1,448 of the 1,724 domains left after our title filter. On 53, Zeta rejected the partner ID; on 32 it returned an empty tag. Neither runs anything, so those 85 are out. So are 8 sites carrying someone else's account: 6 bank sites tagged with their marketing agency's pixel, a copy of CNN's homepage on an unrelated domain, and a charity page carrying another organisation's campaign pixel. That is 93 removed, 5.39% of the base.

Sales signal: a Rezync list built from the script alone carries dead pixels, Weight Watchers' 11 domains among them. Ask whether the pixel still answers before you treat a domain as a Zeta account.

One reading, and the exits we can count

The chart shows one point, October 2026, because it is the first month counted on the cleaned base. Earlier totals wouldn't give a clean trend anyway: the domains we crawl turn over every month, dead sites out and newly found ones in, and our detection widens as we go. Exits are clearer. 570 domains dropped the pixel on at least one hostname since we began tracking it on 4 August 2026, and 124 of those still run it elsewhere, which leaves 446 that removed it from every hostname we crawl.

"Rezync looks like a mid-sized retargeting tag until you read the account names. Then it becomes a few hundred US brands, each with a long list of domains." - Elif Arslan, CMO & Co-founder at TechnologyChecker.io

Sales signal: the 446 full removals are worth a look for any rival platform. A brand that pulled Zeta's tag from all its sites has changed something in its marketing stack.

Accounts, not domains

This is the part that changes how you use the list. The 1,355 domains with a readable, working pixel belong to just 376 Zeta accounts, and 193 of those accounts sit on one domain each. At the other end, 21 accounts cover 10 or more domains, 632 domains between them. Lithia Auto Group's account runs on 119 dealership sites and AutoNation's on 91, together 12.88% of the 1,631. The Salvation Army (55), Ethan Allen (41) and Dairy Farmers of Wisconsin (40) follow. Carmakers do the same in Europe: Lexus Netherlands' account sits on 17 dealer domains and Toyota Poland's on 9.

Sizes need reading with that in mind. 30.59% of matched companies have 1 to 10 staff and 23.03% have 11 to 50, but many are a single dealership, dental practice or hotel whose pixel belongs to a parent group. At the top, 14.8% have more than 1,000 staff. The companies are old, too: 24.38% were founded before 1960 and only 5.47% in the 2020s. Named users I checked in a browser, with the pixel answering, include AT&T, USPS, Ulta Beauty, Vanguard, Travelers, Citi, Purdue University and the Salvation Army.

Sales signal: sell to the account, not the domain. One conversation with Lithia's or AutoNation's marketing team covers more than two hundred sites.

Retail, car dealers and the non-profit sector

The base is American: 818 matched companies are in the United States, then Canada with 30, Hungary with 11 and the United Kingdom with 10. Retail leads the industries at 19.9%. Car sales are the second block once you add two LinkedIn labels: Motor Vehicle Manufacturing (7.91%) and Automotive (3.34%) make 11.25%, mostly dealer sites. Hospitality follows at 6.3%, then Non-profit Organizations at 5.19% and Financial Services at 4.08%.

Sales signal: automotive, banking and non-profit fundraising are the three verticals where Zeta's tag is already established. Vendors selling into those teams can open with the identity data they already pay for.

Next to other ad tags

We have no switching data for Rezync, and the category table is an imperfect yardstick: RTB House (49,530 domains) and Seznam Sklik (14,269) sell retargeting as a service, while the Zync pixel is one piece of Zeta's platform. What our crawl does show is stacking. Of the 1,631 domains, 102 also run Criteo, 75 AdRoll, 45 Bidtellect Universal Pixel and 38 RTB House.

"On Rezync sites, ad tags pile up: Criteo, AdRoll and RTB House sit beside Zeta's pixel rather than in its place. The stack tells you more than the category rank." - Elif Arslan, CMO & Co-founder at TechnologyChecker.io

Sales signal: competitors don't need to displace Zeta to win budget here. These advertisers already pay several ad-tech vendors at once.

The stack around it

Shares here are of the 1,631 domains on this page. One row needs explaining first: Rocket Fuel on 59.78% is rfihub.com, which Zeta's tag documentation lists as its own programmatic tag, so it rides along with the Zync container rather than being a separate purchase. DoubleClick Floodlight (59.78%), Microsoft Advertising (54.38%) and The Trade Desk (41.26%) point to heavy paid media. Invoca is on 14.96% and Adobe Analytics on 14.1%. OneTrust leads consent at 20.91%, ahead of Osano at 7.66%.

Sales signal: this is an enterprise media stack. Expect procurement, legal review of data sharing and an agency in the room.

What Zeta says, and what we see

Zeta's privacy guidelines say the Zync pixel fires when someone opens an advertiser's page, places a Zync cookie and lets Zeta link cookie IDs to MD5-hashed email addresses, which it matches against its clients' permissioned data to retarget visitors. The cookie table lists the zync-uuid cookie for six months. Our data adds the customer side: a few hundred mostly American accounts, many of them older brands with a long list of domains.

Sales signal: privacy and consent questions come up early with these buyers, and 20.91% of the sites already run OneTrust.

Key takeaways

1. Rezync is Zeta Global's Zync pixel, not a separate vendor.
2. 1,631 domains after removing 93 dead or borrowed pixels; 942 matched companies, 818 of them American.
3. 376 accounts own the 1,355 readable pixels; Lithia and AutoNation alone cover 210 domains.
4. The buyers are older and larger than most retargeting users: 24.38% founded before 1960, 14.8% with more than 1,000 staff.
5. The stack is enterprise paid media: Floodlight, Microsoft Advertising and The Trade Desk on 41% or more.

How to use this list

Outreach template: "Your sites run Zeta's Zync pixel alongside The Trade Desk and Microsoft Advertising. Which of those tags gets credit for a sale?"

Targeting: group domains by Zeta account before you count prospects, then filter for retail, automotive and financial services in the United States.

Competitive angle: follow the 446 domains that removed the pixel everywhere we crawl, and the accounts whose pixels Zeta reports as dead.

The full list of 1,631 domains, with company size, industry, country and stack, is on TechnologyChecker.io.