Who are the top identity graph providers in 2026?

By access model, on the pages we checked: LiveRamp works through its platform and clean room, and Acxiom brings its applications to your data; Experian, TransUnion and Epsilon did not state an access model; BIGDBM lists daily email-to-MAID files, GSDSI licenses MAID-to-HEM files, and Throtle lists a deterministic graph on Datarade; FullContact resolves records by API or batch; ID5 and UID2 are shared IDs for ad tech. The right one depends on how you need access.

What is MAID-to-hashed-email data?

A file that links mobile advertising IDs (Apple IDFA, Google GAID) to hashed email addresses. Marketers use it to onboard CRM lists to mobile and CTV, and to resolve devices to people or households for measurement. See Identity Graphs 101.

Which identity graph providers sell a file rather than a platform?

Among the providers compared here, BIGDBM lists email-to-MAID linkages on Datarade, and GSDSI licenses a MAID-to-HEM file directly. On the pages we checked, LiveRamp works through its platform and clean room, and Acxiom brings its applications to your data, rather than selling a file.

Is a hashed email anonymous?

No. The FTC said in July 2024 that hashing does not make data anonymous. Treat hashed emails and linked device IDs as personal data. This is general information, not legal advice.

Is UID2 an identity graph?

No. UID2 is a shared ID standard used in ad tech, not a dataset you license. Our UID2 vs RampID comparison covers how it works.

How should I test an identity graph provider?

Send every finalist the same sample of your own customer records, then score match rate, MAIDs per person, recency and false links, and repeat a month later to measure decay. Agree the weights before the files arrive.

Where does GSDSI fit among identity graph providers?

In the licensed-file group. GSDSI licenses ~200M+ U.S. MAID-to-HEM pairs and 700M+ international devices across 150+ countries, refreshed daily. Request a sample from the MAID Feed page and test it beside the others.

Top Identity Graph Providers 2026: 11 Compared

People searching for identity graph providers usually want names, so this guide starts with eleven. Each provider is described from its own public pages or its partners' announcements, and each sourced fact links to where it came from. GSDSI sells a MAID-to-hashed-email file, so read this as a vendor's guide: neither the list nor its order is a ranking. The biggest difference between these companies is not size. It is how you get access. Some are described as available through the provider's own platform, clean room or your environment. Some are sold as files you load into your own warehouse. Some are APIs that resolve the fragments you send, and one is an open ID standard rather than a company's graph. For how the linkage works, start with Identity Graphs 101.

Top identity graph providers in 2026, compared

Each row below uses the provider's own public pages, a partner's announcement or, where labelled, a marketplace listing the provider supplied. Scale is shown exactly as each provider states it. Where we did not find something, the cell says "Not found on the pages we checked" rather than guessing. GSDSI appears as one option, described only from what our own MAID Feed page publishes.

11 identity graph and MAID-to-hashed-email providers compared (sources compiled October 2, 2026)

Provider	Scale as stated	Identifiers it links	How you get access	Licensed as a file?	Best fit (our view)
LiveRamp (RampID)	States PII maintained on 245 million individuals in the U.S.	Emails, phone numbers, postal addresses, device IDs and authenticated logins, resolved deterministically to a RampID	Through LiveRamp; its clean room resolves data to RampIDs, with PII optionally removed	Not as a raw graph file, on the pages we checked	Activating your own customer data through LiveRamp
Experian (Digital Graph)	The U.S. Digital Graph contains 4.2 billion digital identifiers, 300 million CTV IDs, and 250 million individuals	MAIDs, CTV IDs, universal IDs and hashed emails	Not found on the pages we checked	Not found on the pages we checked	Extending your own IDs across devices and CTV
TransUnion	Its January 2024 graph update states coverage of 98% of the U.S. adult population	Phone numbers, email addresses and IP addresses linked to households, plus hashed emails linked to physical addresses	Not found on the pages we checked. AdExchanger reported in 2021 that TransUnion had agreed to acquire Neustar	Not found on the pages we checked	Resolution that combines offline and online identifiers, from a credit bureau
Epsilon (CORE ID)	Describes a COREid graph grounded in offline name and address; ask for a dated count	Offline name and address, per its own page	Not found on the pages we checked. Publicis acquired Lotame in 2025, which AdExchanger said would live within the holdco for its Epsilon consumer data segment	Not found on the pages we checked	Brands buying media through the Epsilon and Publicis stack
Acxiom (Real ID)	States 260M U.S. consumers and a 2.6B global audience	Consumers and audiences, per its own page	Its cloud architecture brings Acxiom's applications to your data to reduce data movement	Not as a raw file, on the pages we checked	Brands that want a referential graph kept inside their own environment
Throtle	Its Datarade profile states 250M U.S. individuals and 130M U.S. households (seller-supplied)	Individuals and households, with 100% deterministic matching per its profile	Listed as a data provider on Datarade; ask for licence terms	Not found on the pages we checked	A U.S. identity graph that its profile describes as deterministic
FullContact	No scale figure found on the pages we checked	CRM, call center, mailing address and other customer data, resolved to a persistent PersonID	API or batch (Resolve)	Not found on the pages we checked	Resolving your own records by API or batch
ID5	Figures differ between sources; ask ID5 for a dated count	ID5 describes shared identifiers it distributes to the ecosystem, with consent-based encryption	Not found on the pages we checked, which describe a shared ID	Not found on the pages we checked, which describe a shared ID	Publisher and DSP addressability rather than a MAID-to-HEM file
UID2 (a framework, not a vendor graph)	Not applicable	A shared ID standard used in ad tech; see our UID2 vs RampID comparison for how it works	Through platforms that support it; see the UID2 vs RampID comparison	Not applicable	Cookieless addressability across platforms that support it
BIGDBM	Its listing states 8 billion records, with files updated daily (seller-supplied)	Observed linkages between emails and MAIDs from website and device activity	Datarade listing; licence terms not stated	Files updated daily, per its listing	Buying a U.S. MAID-to-email file for onboarding
GSDSI	~200M+ U.S. MAID-to-HEM pairs and 700M+ international devices across 150+ countries	Apple IDFA and Google GAID linked to hashed emails, with app activity and interest segments	A licensed file or API in CSV, JSON or Parquet, refreshed daily	Yes, licensed directly to the buyer	Teams that want a MAID-to-HEM file in their own warehouse, tested on a sample first

Read the scale column with care. Experian, Throtle and LiveRamp count individuals, Acxiom counts consumers, and BIGDBM counts records. Experian adds digital identifiers and CTV IDs, and Throtle adds households. TransUnion states a share of U.S. adults. Several figures carry no date, and two listings are written by the sellers themselves. None of these numbers can be ranked against the others, so ask each finalist for a dated figure in the unit you care about, in writing.

Four ways to access an identity graph, and why it matters

Inside a provider's platform or your environment. On the pages we checked, LiveRamp describes access through its platform and clean room, and Acxiom brings its applications to your data, rather than a graph file. We did not find an access model for Experian, TransUnion or Epsilon, so ask them.
As a file. BIGDBM lists email-to-MAID files updated daily, and GSDSI licenses MAID-to-HEM files you load into your own warehouse; Throtle lists a deterministic U.S. graph on Datarade, so ask how it is delivered. You hold the rows, so you also hold the compliance duties that come with them.
By API or batch. FullContact resolves the records you send to a persistent PersonID. Suited to enrichment at the moment of capture.
As a shared ID. ID5 distributes shared identifiers to the ecosystem, and UID2 is a shared ID standard. They make inventory addressable; they are not a dataset you buy.

GSDSI sits in the file group as a licensor. Our MAID Feed links mobile ad IDs to hashed emails, and buyers often pair it with the Core Email File when they need postal and email records alongside device IDs.

How to choose an identity graph provider by job to be done

Onboarding a CRM list to mobile and CTV: a licensed MAID-to-email file (BIGDBM, GSDSI) or a platform onboarder such as LiveRamp. Ask whether you need the rows or only the matched audience. See audience targeting.
Household resolution for measurement: Experian, Acxiom or TransUnion for household-level graphs, joined to exposure data for cross-channel measurement.
Resolving your own records: FullContact, by API or batch.
Cookieless addressability for a publisher or DSP: ID5 or UID2.
Staying inside one holding company's stack: Epsilon for Publicis clients.

Methodology and sources

GSDSI sells a MAID-to-hashed-email file, so we have an interest in this category; the table is a list, not a ranking. The facts were compiled on October 2, 2026 from each provider's own public pages, partner announcements, and, where labelled, marketplace listings written by the seller. Each fact links to the page it came from. Figures are shown as each provider states them and are not converted or averaged. Where sources disagreed, as with ID5's user count, we left the figure out rather than pick one. "Not found on the pages we checked" means exactly that, not that the provider lacks it. The "Best fit" column is our opinion. Providers can email corrections to info@gsdsi.com, and we will update the row with a link to the new source.

The legal context for identity data, as of October 2026

Two points shape how a careful buyer handles a MAID-to-hashed-email file. First, hashing is not anonymization. The FTC's technology blog said so directly in July 2024 in No, hashing still doesn't make your data anonymous. Treat hashed emails and the device IDs linked to them as personal data in contracts, retention rules and deletion handling.

Second, device-linked data has a recent enforcement record. In January 2025 the FTC finalized an order against Gravy Analytics and Venntel that prohibits selling, disclosing or using sensitive location data except in limited national security or law enforcement cases. The FTC announced a proposed settlement with Kochava in May 2026, and a federal judge in Idaho signed an order on June 25, 2026 that bars Kochava and Collective Data Solutions from selling, sharing or disclosing sensitive location data, subject to the order's conditions. Both cases concerned sensitive location data. Ask every provider how consent was captured, how deletion requests reach the files you already hold, and which uses are permitted, then put the answers in the contract. Our guide to data licensing agreement red flags lists the clauses. This section is general information, not legal advice.

What to ask every identity graph provider

Identity graph provider evaluation criteria

Criterion	What to ask	Why it matters
Access model	Do I receive rows, a matched audience, an API response or an ID?	It decides who holds the data and who carries the compliance duties
Deterministic or probabilistic	Which links come from logins or verified records, and which are modelled?	Modelled links raise reach and lower precision
Unit and date of scale	Is the figure people, households, MAIDs or events, and as of when?	Figures in different units cannot be compared
Match rate on my data	What share of my sample matched, and how many links per person?	Coverage claims only matter where they overlap your customers
Freshness and decay	How often are links refreshed, and how fast do stale MAIDs drop out?	Device IDs churn; see graph decay
Consent and deletion	How was consent captured, and how do deletions reach delivered files?	Recent FTC orders turn on consent and sensitive uses
Rights	Are activation, modelling, resale to clients and retention covered?	Platforms and file sellers grant very different rights

Test design: measure match rate before you sign

Pull a sample of your own customer records with known outcomes, and hash the emails the way each provider expects.
Send the same sample to every finalist under the same rules, as described in seed-match testing.
Score match rate, MAIDs per person, and the share of MAIDs seen in the last 30 days.
Check a slice by hand against data you trust, such as app logins, to estimate false links.
Repeat the match a month later to measure decay, and write the scoring weights down before the files arrive.

Our identity graph buyer's checklist and the guide to match-rate and decay terms in contracts cover the contract side.

Where GSDSI fits

GSDSI licenses ~200M+ U.S. MAID-to-HEM pairs and 700M+ international devices across 150+ countries, sourced from consent-verified mobile applications and SDK partners. The file links Apple IDFA and Google GAID to hashed emails, with app activity and interest segments, refreshed daily and delivered as CSV, JSON, Parquet or API. It is a file for your own warehouse, not an onboarding platform or an open ID. If that is what you need, request a sample through the MAID Feed page or the identity graph overview, and run it through the same match test as every other finalist.

Frequently Asked Questions

Who are the top identity graph providers in 2026?: By access model, on the pages we checked: LiveRamp works through its platform and clean room, and Acxiom brings its applications to your data; Experian, TransUnion and Epsilon did not state an access model; BIGDBM lists daily email-to-MAID files, GSDSI licenses MAID-to-HEM files, and Throtle lists a deterministic graph on Datarade; FullContact resolves records by API or batch; ID5 and UID2 are shared IDs for ad tech. The right one depends on how you need access.
What is MAID-to-hashed-email data?: A file that links mobile advertising IDs (Apple IDFA, Google GAID) to hashed email addresses. Marketers use it to onboard CRM lists to mobile and CTV, and to resolve devices to people or households for measurement. See Identity Graphs 101.
Which identity graph providers sell a file rather than a platform?: Among the providers compared here, BIGDBM lists email-to-MAID linkages on Datarade, and GSDSI licenses a MAID-to-HEM file directly. On the pages we checked, LiveRamp works through its platform and clean room, and Acxiom brings its applications to your data, rather than selling a file.
Is a hashed email anonymous?: No. The FTC said in July 2024 that hashing does not make data anonymous. Treat hashed emails and linked device IDs as personal data. This is general information, not legal advice.
Is UID2 an identity graph?: No. UID2 is a shared ID standard used in ad tech, not a dataset you license. Our UID2 vs RampID comparison covers how it works.
How should I test an identity graph provider?: Send every finalist the same sample of your own customer records, then score match rate, MAIDs per person, recency and false links, and repeat a month later to measure decay. Agree the weights before the files arrive.
Where does GSDSI fit among identity graph providers?: In the licensed-file group. GSDSI licenses ~200M+ U.S. MAID-to-HEM pairs and 700M+ international devices across 150+ countries, refreshed daily. Request a sample from the MAID Feed page and test it beside the others.