Understanding identity resolution in Klaviyo

You will learn

Learn about identity resolution in Klaviyo, which consolidates customers’ interactions across multiple channels under a single record.

Since Klaviyo is an omnichannel marketing tool that supports email, SMS, and mobile push notifications, your customers may interact with you through either or all of these channels. To ensure that your customer profiles remain up to date with activity across all these channels, Klaviyo automatically resolves the identities of different profiles that share a common identifier based on the existing data in your account.

What is identity resolution?

Identity resolution refers to the process of maintaining a unified customer record, regardless of the various identifiers (e.g. email, phone number, etc.) used across different touchpoints or devices. This results in a singular, comprehensive profile for each individual person, irrespective of the channels they interact through.

Identity resolution is often used as a general term that encompasses 2 key data tracking and unification processes:

• Identifying customers
  Recognizing who someone is based on an identity they have provided, or other digital signals.
• Resolving profiles to a single identity
  Consolidating behaviors to identities and de-duplicating records to create a unified view of the customer.

A common example of this is when a customer that has an email profile in your Klaviyo account later subscribes to SMS through a method that is not associated with their email, like a keyword opt-in. This customer action results in a separate profile for receiving SMS messages. However, if a later action sends both their phone number and email address to Klaviyo together, such as a purchase that includes both identifiers, Klaviyo can link the phone-only profile to the email profile and merge them.

Identifying customers

Klaviyo automatically cookies and captures identities from customers through a few different methods.

Onsite JavaScript tracking

Klaviyo's onsite tracking is responsible for tracking the Active on Site and Viewed Product events across your entire website for identified browsers.

Additional Shopify tracking via Shopify Server Pixel

For Shopify users, you can also easily enable new tracking events such as Added to Cart, Viewed Page, Viewed Collection, and Submitted Search through the Shopify pixel. These events sync server-side, providing more complete profiles with more events syncing and flows triggering in Klaviyo.

Forms

Sign-up forms allow you to serve targeted forms and collect customer emails and phone numbers. These are an important part of growing your list and subscriber base. When customers submit a Klaviyo form, their browser is automatically identified via Klaviyo's onsite tracking so you can view the actions that they take on your website.

Message click-through

When a recipient clicks a link to your website in a Klaviyo email, their browser is identified so you can see where they land on your site and track other onsite actions going forward. This requires email to website tracking to be enabled and Klaviyo.js to be running on your website.

Checkout identification

When visitors go through checkout on your website, Klaviyo automatically identifies them and collects checkout events.

Resolving profiles to a single identity

Klaviyo resolves customer identities through 2 main methods.

Anonymous visitor activity backfill

With Klaviyo’s anonymous visitor activity backfill, you can capture onsite activity for a shopper prior to identification. Once that visitor is identified in the future, you’ll have access to their historical onsite events. This allows you to have a more complete view of your customers’ journeys, and enrich customer profiles with historical data. Only activity that was captured and is still available in that browser’s local storage can be backfilled. Learn more about Klaviyo’s anonymous visitor activity backfill.

To collect anonymous visitor activity, you must have Klaviyo.js installed on your store (which is automatic for most integrations). Klaviyo.js allows you to publish Klaviyo sign-up forms and track shoppers’ activities on your website.

Once Klaviyo.js is successfully installed on your website, you can enable anonymous visitor activity backfill in your account settings.

You need permission to edit data settings to change anonymous visitor tracking. To enable anonymous visitor activity backfill:

1. Select your account name in the lower left.
2. Select Settings.
3. Select Data.
4. Under Onsite identification, check Anonymous backfill.

5. Click Save.

Deterministic profile merging

Deterministic profile merging refers to a proactive check that merges 2 separate profiles when an action occurs linking an email address, phone number, or anonymous mobile app ID (iOS or Android) together. This includes merging data across multiple devices, and allows you to effectively manage omnichannel customer data.

How identity resolution works in Klaviyo

As customers interact with your brand across different channels, Klaviyo checks for opportunities to merge these engagements under a single customer profile.

This is based on a process called "identifier precedence," where Klaviyo uses existing data to determine if these omni-channel engagements can be consolidated under a single, stronger identifier.

Klaviyo ranks these identifiers as:

1. Profile ID
   The primary identifier Klaviyo assigns to each profile.
2. External ID
   An external ID that can be used as a primary identifier on the profile, typically in place of an email address. External IDs are set through some integrations (e.g. BigCommerce), or through Klaviyo’s APIs.
3. Email
   The email address associated with a profile.
4. Phone number
   The phone number associated with a profile.
5. Anonymous mobile app ID
   For mobile app profiles, if Klaviyo cannot associate the user with an email address, an anonymous mobile app ID will represent the iOS or Android guest profile.

When Klaviyo creates an anonymous mobile app ID, all of the following ID types are considered:

• IDFA or Push Token on iOS.
• Google Ad ID (GAID), Firebase ID (FID) or Device ID on Android.

For lower-ranking phone numbers and anonymous mobile app IDs, Klaviyo checks if a profile exists within the account recognized only by that identifier. If such a profile is found and can be associated with a higher-ranking identifier based on an instance where they were linked together, Klaviyo will attempt to merge under the higher-ranking identifier.

To illustrate this, below is an example where Klaviyo is resolving the identity of a customer with the following set of identifiers:

Once Klaviyo sees all 3 identifiers together, which indicates they all belong to the same customer, it will check if there is a profile only identified by phone number or only identified by an anonymous mobile app ID. If either is found, they will be merged into the profile with the higher-ranking identifier, in this case email.

Data that triggers a profile merge

For Klaviyo to identify that multiple profiles belong to the same customer, the identifiers associated with each profile need to be recognized together. Often, this information comes in the form of an event, where the event data includes multiple identifiers like email and phone number. Klaviyo also merges profiles based on data that customers submit themselves (e.g., through a form that has fields for both phone and email).

Klaviyo merges profiles based on information submitted through web tracking as well, which associates an activity to an email profile using cookies. For example, if an email profile submits a phone-only form with their cookie present, then the phone number they submit will be appended to their pre-existing profile.

Find a profile ID

Every profile has a unique ID that you can find by navigating to the profile and looking at the URL. Look for the 26-character ID, as illustrated in the image below.

Some older profiles in your account may have a 6-character ID if you acquired them prior to this Klaviyo change. This ID is still correct and unique to their profile.

Manually merge profiles

If you know that a pair of profiles belongs to a single customer, you can manually merge the 2. The destination profile you select keeps its profile ID, and the source profile is removed. If both profiles have an email address, the destination profile’s email remains the primary email.

You need permission to edit profiles to merge them. To manually merge a profile:

1. Navigate to the source profile you want to remove.
2. Open the Profile actions dropdown.
3. Click Merge profile.
   

4. In the pop-up, enter the destination profile’s name, email address, phone number, or external ID, then press Return or Enter to search. This is the profile you want to keep.
5. Select a profile from your search results.
   • If you don’t see the destination profile you’d like to merge into, make sure there are no typos in your search. Then hit the Return or Enter key to search again.
6. Click Merge profiles to confirm. Klaviyo opens the destination profile while the merge processes.

For more information, head to our guide on how to delete, merge, and export a profile.

Additional resources