Identity Resolution: The Secret to a 360-Degree Customer View

Learn how identity resolution platforms aggregate customer data across all touchpoints and channels to give you in-depth insight into their behaviors.

Best Practices
February 16, 2024
Anuj Sharma headshot
Anuj Sharma
Sr. Customer Success Architect
person's hand making a purchase

Identity resolution is the process of creating a holistic customer profile by collecting information from all data sources and touchpoints they have with your business.

Companies have access to vast amounts of customer data, which is vital for providing the personalized experiences consumers have increasingly come to expect. The trick is connecting all data from multiple sources, like e-commerce websites and mobile apps, into a single view of the customer—and identity resolution can help.

Identity resolution helps companies create better customer experiences and deliver more personalized marketing campaigns throughout the customer journey.

Key takeaways
  • Identity resolution is the process of gathering old and new customer data and using it to develop a single, unified view of the user.
  • Identity resolution provides more insight into your customers and helps you create more targeted marketing campaigns and personalized user experiences.
  • Specialized software and tools, like Amplitude CDP, make the identity resolution process possible, particularly when using deterministic matching.

What is identity resolution?

Identity resolution connects all the information on how a customer behaves and interacts with your business into a unified customer identity or profile. These behaviors and interactions can include any of the following:

  • Browser activity.
  • Purchase history.
  • Type of device used.
  • IP addresses.
  • Physical addresses.
  • Demographics.
  • Personal data, including phone numbers, email addresses, and unique customer ID numbers.

You can unify all these data points into a single customer profile to create an accurate 360-degree view of the customer. That way, you can interact with customers in a way that boosts engagement, retention, and loyalty.

Unifying this data can be tricky, given customers' multiple touchpoints with your product. The average US household has 22 connected devices—that means 22 different physical devices from which customers can interact with you. Customers can access multiple touchpoints with you on each device, from web browsers and apps to social media and email.

Apart from the complexity of gathering all this data, companies are also navigating an ever-changing data privacy landscape. For example, working within regulatory legislation like the California Consumer Privacy Act (CCPA) and the imminent phasing out of third-party cookies.

You can use identity resolution solutions or platforms to successfully collate customer data across multiple platforms while remaining legally compliant.

Identity resolution software and tools

Tackling the complexity of identity resolution requires an identity resolution platform to capture, store, and unify your customer data. There are several identity resolution tools out there, and most offer the following core features and capabilities:

  • Data onboarding: All online and offline customer data is quickly, accurately, and securely transferred into the same system.
  • Proprietary identity graphs: A process to enrich a given user profile with unique associated identifiers and events, including third-party, publicly available, and device data and IP address information. It can also include user-provided personal identifiable information (PII) and identifiers like email addresses, consented cookie identifiers, phone numbers, etc.
  • Real-time and persistent matching and resolution of data: Identity resolution of customer data platforms (CDPs) will gather all the data and begin a process of deduplication, matching, hashing, anonymizing, and suppression. This ensures the final user profile is accurate and that any changes are automatically updated in real-time.
  • Integration with third-party systems: APIs connect with other systems, such as martech and adtech platforms, to further enhance the data.
  • Compliance features: These systems ensure that your identity resolution efforts remain within data privacy and security regulations.

Identity resolution happens in two places—in data warehouses and customer data platforms.

Data warehouse (DWH)

The data warehouse is the starting point of your identity resolution process. The DWH consumes information from first-party data sources like websites and apps, usually through an external customer data infrastructure (CDI) solution. It then matches data in one of two ways—probabilistic matching or deterministic matching.


Probabilistic matching

Probabilistic matching happens in the absence of identifiers (IDs). IDs are anything from email, device IDs, mobile numbers, and user IDs that can match and merge all omnichannel user information. Probabilistic mining relies on signals or a combination of user properties, like name, location, and operating system (OS), merging them to see if the potential match attains an acceptable score.

Probabilistic matching is not 100% accurate, and we only recommend using it in critical use cases, such as detecting fraud within large and complex datasets.

Deterministic matching

We turn to deterministic matching to develop better user experiences and personalized marketing strategies. This matching uses available identifiers through customer data platforms for more accurate identity resolution.

Customer data platform

Customer data platforms (CDPs) enable you to segment and sync data with third-party tools through a visual interface. Shortly after the data is collected, a CDP performs deterministic matching based on the available identifiers (IDs).

PII enables a high level of accuracy through deterministic identity resolution. Customer data platforms, like Amplitude CDP, help meet your identity resolution needs because:

  • All data collected comes directly from the customer, making them best suited for personalization.
  • They are privacy-friendly. If a customer opts out of marketing communications or wishes to be forgotten, you can accurately identify them across all systems and remove their data.

What can identity resolution help you learn?

Incorporating identity resolution into your data strategy is the best way to understand your customers clearly. It allows you to create more engaging customer experiences and develop more effective, people-based marketing strategies.

  • Enhance the user journey and create more personalized and consistent customer experiences. Even as you obtain customer data from multiple sources, you should ensure customers have consistently positive experiences regardless of their platform or operating system. If an established user suddenly changes from an iOS to an Android device, they expect to continue receiving the same personalized experience.
  • Create better marketing campaigns. The most effective marketing campaigns are based on accurate customer data. If an existing customer logs into their profile from a different device and is wrongly classified as a new user, you could mistakenly target them with prospect-focus marketing messaging. This error would waste your resources and reduce the quality of the customer’s experience.
  • Obtain valuable insight on unknown, new, or unregistered website visitors. New e-commerce site customers will likely browse before purchasing and create an account upon checkout. Without identity resolution, your data management system differentiates between logged-out and logged-in users, and you miss out on valuable insight into their pre-registration buying behavior. But with identity resolution, you can aggregate all this data.

How to implement identity resolution

Before beginning the identity resolution process, we recommend selecting the right vendor. Some vendors work with deterministic identity resolution, while others use probabilistic methods. As we discussed above, a deterministic approach to identity resolution means you create profiles more accurately using first-party data.

After making this critical first choice, you can perform your identity resolution process using the following five steps:

  1. Determine all the touchpoints that make up your customer's journey, including different channels, platforms, and devices.
  2. Identify the timeline and the paths customers take in a typical journey.
  3. Aggregate and match every device and platform to their respective individual through a defined set of attributes.
  4. Validate your data to ensure the information you obtained above is, in fact, correct.
  5. Once you validate the data, activate it to create personalized and engaging experiences and messaging campaigns based on the insights you have obtained.

Tackling identity resolution with Amplitude

Successful marketing campaigns require one holistic view of the customer, and identity resolution is the missing link between all your data sources and the touchpoints a customer has with your business. Regardless of where you are on your journey to creating one view of the truth for your customers, Amplitude can help.

Amplitude CDP helps world-class organizations around the world, like AllTrails, centralize user data onto a single platform to deliver more personalized experiences that ultimately drive higher conversion rates.

Learn more about identity resolution in Amplitude CDP by speaking with a product expert.

About the Author
Anuj Sharma headshot
Anuj Sharma
Sr. Customer Success Architect
Anuj is an experienced Solutions Architect with a background in consultation on CDPs and customer data management. He's skilled in consulting on REST APIs, SDK instrumentation, building data taxonomy and data quality management.

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