A real-time identity graph and a persistent identity graph differ in how they resolve and store identity data. A real-time graph matches identifiers on the fly, delivering instant recognition during live interactions. A persistent graph maintains a continuously updated record of known identities over time. Both serve distinct purposes, and understanding the difference helps you choose the right approach for your use case.
How does a real-time identity graph resolve identities differently?
A real-time identity graph resolves identities at the moment of interaction, matching incoming signals such as email addresses, device IDs, or cookies against a broader identity graph to recognize an individual instantly. This happens in milliseconds, without requiring prior knowledge of that specific user stored in your own system.
Rather than relying on pre-built customer records, a real-time graph queries live connections across a network of identity data sources the moment a signal arrives. This makes it particularly powerful for recognizing anonymous or partially known visitors the instant they land on a website, open an app, or engage with an ad.
The practical benefit is immediacy. When a user arrives with only a hashed email or a device identifier, a real-time identity graph can connect that signal to a broader profile and return enriched insights before the page even finishes loading. This enables personalization, fraud detection, and audience targeting without waiting for a batch process to catch up.
What is a persistent identity graph and how is it maintained?
A persistent identity graph is a continuously maintained, long-term record that links all known identifiers for an individual into a single, unified profile. Unlike a real-time lookup, a persistent graph accumulates and updates identity connections over time, building a comprehensive view of each person across their digital and offline touchpoints.
Maintaining a persistent graph requires ongoing data ingestion and reconciliation. As new identifiers appear, such as a new device, a changed email address, or an offline purchase, the graph must update existing records and merge or split profiles accordingly. This process relies on several key identity graph data sources:
- First-party data collected directly from customers
- Offline data such as purchase history or loyalty program records
- Cross-device signals that connect mobile, desktop, and connected TV activity
- Authenticated identifiers like email addresses and phone numbers
A well-maintained persistent identity graph becomes more accurate over time, making it the foundation for long-term customer intelligence, segmentation, and audience building across channels.
Which type of identity graph is better for personalization?
For personalization, the most effective approach combines both types. A persistent identity graph provides the depth of customer knowledge needed to deliver relevant experiences, while a real-time identity graph ensures that knowledge is applied at the exact moment it matters most. Neither alone delivers the full picture.
A persistent graph tells you who someone is based on their history. A real-time graph ensures you can act on that knowledge instantly, even when the person arrives through an unfamiliar identifier or an anonymous session. Together, they power a cross-device identity graph that recognizes people consistently whether they are logged in or not, on mobile or desktop, in-store or online.
For identity graph marketing, this combination means you can greet a returning customer with a relevant offer the moment they arrive, rather than treating them as a stranger simply because they switched devices or cleared their cookies.
How FullContact helps with building an identity graph
We built our Resolve platform specifically to bridge real-time recognition and persistent identity in a single, privacy-safe solution. Our identity graph spans over a decade of authenticated and behavioral data, enabling businesses to recognize individuals instantly while maintaining a rich, continuously updated profile for each person. Here is what that means in practice:
- Real-time API responses in under 150 milliseconds for live identity resolution
- 900+ personal and professional attributes appended to customer records
- Persistent identity profiles that connect online and offline data sources
- Privacy-safe architecture that never requires you to share your customer data
Whether you are trying to personalize at the moment of arrival or build smarter long-term audience segments, we can help you put the right identity infrastructure in place. Contact us to explore how our identity graph can work for your business.