Ask two buyers what identity resolution tool they are looking at and you can get answers that share nothing but the phrase. A small apparel brand means a tool that puts an email address to the visitors browsing its site. A media company means the platform that carries its customer file into every advertising system it buys in. A retailer with duplicate profiles means something closer to a customer data platform. Buyers describe all three under the identity-resolution umbrella, but they are not shopping for the same job.
What is identity resolution?
Identity resolution is the work of deciding which records and identifiers belong to the same person — the phone and the laptop, the guest checkout and the signed-in order, the current email address and the one from two years ago. It recognises them as one customer rather than five.
Matching can be deterministic, on shared identifiers such as an email address or a login, or probabilistic, inferred from signals that suggest the same person. Some buyers evaluate identity quality along that line.
What the interviews add is what buyers actually mean when they shop for it:
In these interviews identity resolution clusters around three primary jobs: identifying anonymous visitors on your own site, matching known customers to advertising and media platforms, and unifying records inside your own systems. A smaller fourth group uses the term for server-side tracking and conversion APIs.
The job matters because the vendor sets barely overlap. The visitor job is the most common and skews to small brands; matching to advertising platforms skews to large enterprises.
What is the difference between identity resolution, data onboarding and visitor identification?
Identity resolution is the underlying job; data onboarding and visitor identification are two applications of it, facing opposite directions. Onboarding takes customers you already know outward, onto other platforms. Visitor identification works inward, on people already on your site whom you do not know yet.
Data onboarding matches your first-party customer file to identities on advertising, media and partner platforms, so the same people can be targeted, suppressed or measured there. Visitor identification tries to put a contactable identity, usually an email address, to site visitors who never signed up.
The third job, record unification, faces neither way: it reconciles the records you already hold.
Across all the buyers we interview, the two products barely meet. Companies running a dedicated visitor-identification tool have a median revenue of about $20 million, and most are under $100 million; companies running an onboarding platform have a median of about $4.6 billion. Only one company in the corpus runs both.
Visitor identification
Inward. In these interviews, buyers use these tools to associate otherwise anonymous site traffic with contactable identities, often feeding the identified profiles into email flows. Retention.com, Opensend, Black Crow. Wunderkind does it as part of a wider messaging product, and its buyers sit between the two groups — larger than the visitor-tool buyers, and a quarter of them also run an onboarding platform.
Data onboarding
Outward. Carries the customer file into advertising platforms, with match rate a key measure buyers use to judge it. LiveRamp, Acxiom, Experian, Epsilon. Where the data cannot leave either side, a data clean room is the adjacent structure.
Record unification
Internal. Reconciles duplicate and conflicting records across your own systems into one profile — a need that often leads buyers into evaluating a customer data platform.
Who is buying identity resolution?
This in-market cohort skews smaller than the wider corpus. About a third of the buyers in market for identity resolution work at companies under $100 million in revenue, against about one in five across all the buyers we interview. The most common job in the cohort, visitor identification, also skews strongly toward smaller companies.
The stacks differ too. Klaviyo and Shopify Plus each appear about twice as often as across the corpus, and server-side tracking and post-purchase tools for Shopify brands far more often than that. At the other end, LiveRamp appears more than twice as often as the corpus base rate. Data and analytics titles are about twice as common as they are across the corpus; ecommerce titles are less common.
What do buyers mean when they shop for identity resolution?
Read in full, the interviews tagged to identity resolution cluster around three primary jobs, plus one adjacent use:
- Identify anonymous visitors on the site
- Match the customer file to advertising platforms
- Unify records inside their own systems
- Adjacent: preserve identity signal for ad platforms
The jobs sit in very different company-size cohorts, and very few buyers describe more than one. Only two describe both of the first two.
Identify anonymous visitors on the site
About four in ten of the buyers whose job is clear. Most are small ecommerce brands — median revenue around $40 million — adding an email address to traffic they cannot otherwise reach, and feeding it into abandonment and welcome flows.
A wellness brand is “hoping to capture more anonymous traffic to our site so that we can engage with them, email them, and convert them into customers.” A skincare brand describes the mechanism: “this tech identifies them and puts them into our Klaviyo flows.”
Match the customer file to advertising platforms
About a quarter. These are large enterprises — median revenue around $8 billion — and the job is data onboarding: getting known customers into every platform they buy media in, for targeting, suppression and measurement.
A media company: “we essentially upload our first party CRM onto LiveRamp, and they’re the pipe that essentially pushes out the audiences.”
Unify records inside their own systems
About one in five, mostly large companies — median revenue around $2 billion. The problem is duplicate or conflicting profiles across their own systems, and the shortlist often turns into a CDP evaluation.
A footwear retailer: “We have a problem with duplicate customer profiles being created in various systems, which compromises the integrity of our customer data.” A specialty retailer says simply that “we don’t have a single unified customer database.”
Preserve identity signal for ad platforms
A handful mean server-side tracking and conversion APIs — holding on to identity signal for attribution and ad platforms as cookies weaken. Match rates are the measure here too.
A health and wellness company on its conversion API: “low match rates in particular is one of our biggest challenges.”
Smaller brands often stack several layers of identity on the same site. An apparel brand describes its email platform, two tracking tools and a visitor-identification tool as successive layers: “if your traffic is 100 people, all of that together maybe gets you 30%. So an Opensend is to help you get another 10%.”
Which identity resolution tools do buyers use?
It depends on the job. For data onboarding, LiveRamp is the most-rated platform, at 7.5/10. For visitor identification, Retention.com has the highest observed average, at 7.7/10. Internal record-unification needs in these interviews often lead into CDP evaluations — Amperity, at 7.3/10, is one platform buyers name for identity work, and the full set is on what is a CDP.
| Platform | Avg rating | What buyers here emphasize |
|---|---|---|
| 7.5 | The most-rated platform here. Activation and reach among buyers who rate it highly; match quality and cost among those who do not. | |
| around 7.5 | — | |
| around 7 | — | |
| 6.7 | Email and reach among buyers who rate it highly; return on spend comes up at both ends of the scale. | |
| around 6.5 | — | |
| 6.3 | Support, among buyers who rate it highly. | |
| not rated | Rated by too few buyers to publish a number. |
| Tool | Avg rating | What buyers here emphasize |
|---|---|---|
| 7.7 | Email capture and abandonment flows, raised by half of the buyers who rate it highly. | |
| around 7 | — | |
| around 7 | — | |
| 6.4 | Spans identity and messaging. Email capture and flows among buyers who rate it highly; cost comes up more among those who do not. |
Figures shown as around are rounded because fewer buyers rated those products. TransUnion also comes up as an onboarding and enrichment source, on too few ratings to settle a figure. The two tables are not a single ranking: the tools in them do different jobs for different companies.
How do buyers judge match quality, and what does it cost?
By match rate on the onboarding side, and by how many good extra profiles appear on the visitor side. Price comes up on both sides, but buyers judge quality differently.
Enterprise buyers describe match rates as uneven and leaky. A media company notices “the match rates are different by every platform that we buy in,” and a financial-services enterprise describes “a drop-off as you’re matching the large data set to one vendor to the other” at every hand-off. Smaller brands measure something different: an apparel brand testing a second tool on top of its first wants to see “not only seeing what’s incremental and how many more profiles they identify, but what are the qualities of those profiles.”
On cost, the onboarding complaint is the meter: one enterprise buyer says the platform will “charge every time we use the pipe.” On the visitor side it is whether the economics hold at a small brand’s scale, and whether the tools differ at all — a very small apparel brand says “They’re all using the same 180 million person database.” Compliance is a visitor-side question. An apparel brand that trialled a tool and did not adopt it puts it as a brand decision: “Do they feel comfortable messaging customers who haven’t officially opted in to marketing?”
Match rates, deterministic against probabilistic matching, and what the pricing actually meters are covered in depth in what identity-resolution buyers wish they’d known.
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Start with the gap you actually have — and name it before choosing the category. The questions below are our recommendation rather than a framework buyers describe, built from where the buyers above landed.
First, name the gap. In these interviews, unidentified site traffic maps to visitor-identification tools; matching known customers into advertising and media platforms maps to data onboarding; and duplicate or conflicting records across internal systems often leads buyers into CDP evaluations. Second, what do you already run? Some small brands find their email platform covers part of the job — one says it is “less and less obvious to me at least that we need a tool to do this because Klaviyo does a lot of identification as well.” Third, decide how you will judge it before the trial: match rate by platform for onboarding, and the quality of the added profiles, not just the count, for visitor identification. And for visitor identification, settle your position on messaging people who did not opt in with you before you buy, rather than after.
Common questions
What is identity resolution?
Identity resolution is the work of deciding which records and identifiers belong to the same person — the phone and the laptop, the guest checkout and the signed-in order, the current email address and the one from two years ago. It recognises them as one customer rather than five. Buyers use the phrase for three different jobs: identifying anonymous visitors on their own site, matching their customer file to advertising and media platforms, and unifying duplicate records inside their own systems.
What is the difference between identity resolution and data onboarding?
Identity resolution is the underlying job of determining which identifiers and records belong to the same person. Data onboarding applies that matching outward: it matches a company's known customer file to identities on advertising, media and partner platforms for targeting, suppression or measurement. In these interviews onboarding is a large-enterprise purchase — LiveRamp is the most-rated platform for it — while visitor identification, the other common application, is bought by much smaller companies.
What is visitor identification and how does it work?
Visitor identification tries to put a contactable identity, usually an email address, to people browsing your site who never signed up. In these interviews buyers use these tools to associate otherwise anonymous site traffic with contactable identities, often feeding them into email flows. It is the most common identity job among buyers in market here, bought mostly by small ecommerce brands, and the tools buyers name include Retention.com, Opensend and Black Crow. The concerns they raise are the quality of the extra profiles and whether messaging people who did not opt in with that brand is compliant.
Which identity resolution tools do buyers rate highest?
It depends on the job. For data onboarding, LiveRamp is the most-rated platform at 7.5/10, with Acxiom around 7.5 on a smaller sample, Experian around 7, Zeta 6.7/10, Merkle around 6.5 and Epsilon 6.3/10. For visitor identification, Retention.com has the highest observed average at 7.7/10, Opensend and Black Crow sit around 7, and Wunderkind, which spans identity and messaging, rates 6.4/10. Internal record unification often leads buyers into CDP evaluations instead.
Do I need an identity resolution tool?
Start with the identity gap you actually have. If people browse your site without ever identifying themselves, that is visitor identification; if you know your customers but cannot reach or measure them on advertising platforms, that is data onboarding; if your own systems hold duplicate or conflicting records, that is a record-unification job, which often leads buyers into CDP evaluations. Some small brands also find their email platform already does part of the identifying.
Is identity resolution the same as a CDP?
No. Identity resolution is a capability or job; a CDP is one type of platform that can perform it. In these interviews, buyers with duplicate or conflicting customer records often evaluate CDPs, while buyers trying to identify anonymous site visitors or match customers into advertising platforms consider different tool categories.
What do buyers complain about with identity resolution tools?
Price comes up on both sides: onboarding buyers describe being charged every time they use the platform, and smaller brands question the economics of visitor identification. Match quality comes next — match rates that differ by platform and drop at each hand-off on the enterprise side, and uncertain quality of the extra profiles on the visitor side. Compliance concerns are concentrated in visitor identification, and some smaller brands see those tools as interchangeable.
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