Understand data transformation in Klaviyo
You will learn
Learn about the data transformation tool in Klaviyo, and how you can use it to make your data more useful.
Advanced KDP is a paid add-on to Klaviyo’s standard marketing application. Data transformation is also available during an active Advanced KDP trial. See our billing guide to learn how to purchase this plan.
Transform data
The following roles can create, edit, and delete transformations:
- Owner
- Admin
- Manager
To transform data in Klaviyo:
- Navigate to Data management > Transformation in the Advanced section, then select the Profile properties tab.
- To use a pre-built transformation, select one from the pre-built options. If you already have transformations, select Create to view those options. To start from scratch, select Create on the page showing the pre-built options.
- If creating your own transformation, select a Method. For Format or Standardize, choose the Profile property you want to transform. For Merge, select the properties to combine in the merge rules.
- Configure the rules for your chosen method, as described under Transformation methods below. For a pre-built transformation, review the preset rules and edit them if needed.
- Select Save. Your transformation appears in the transformation list while Klaviyo applies it to existing profiles.
Transformed values are saved in a new profile property with the suffix __transformed (2 underscores). For example, Property becomes Property__transformed. For a merge, the first property in the list supplies the new property name. The original properties and their values are preserved.
Additional transformations cannot be applied directly to a transformed property such as Property__transformed. To use another transformation method, select the original property.

Transformation methods
The data transformation tool in Klaviyo allows you to make the following transformations to your profile property values:
- Format
Reformat profile property values. - Standardize
Set rules to automatically replace specific profile property values. - Merge
Merge multiple custom profile properties into 1 property
You can apply 1 Format transformation and 1 Standardize transformation to each original profile property.
Transformations to profile property values apply to all existing profiles and will continue applying on an ongoing basis.
Format
The Format transformation method has 5 formatting options:
- Remove spaces
Deletes spaces at the beginning and end of values (e.g., “ ABC” to “ABC”). - Remove quotes
Removes straight single or double quotation marks at the beginning and end of values (e.g., "ABC" to ABC). - Remove special characters
Removes characters other than English letters and digits, including spaces, punctuation, and accented letters (e.g., A,B,C to ABC). - Capitalize the first letter of every word
Capitalizes the first letter of each word (e.g., John doe to John Doe). - Revise date format
Store dates in a consistent format. Choose Date only or Date and time. The transformed values are stored asYYYY-MM-DDorYYYY-MM-DD HH:MM:SS, but how they appear in the app depends on your locale. Values that cannot be interpreted as dates are left blank in the transformed property.
You can combine any of the 4 text formatting options. Revise date format must be used on its own and cannot be combined with the text formatting options.

When you combine text formatting rules, they are applied in the following order:
- Remove spaces
- Remove quotes
- Remove special characters
- Capitalize words
Example Format transformation
In this example, the Format transformation is being applied to the Name profile property in Klaviyo using the formatting rules:
- Remove spaces
- Remove special characters
- Capitalize the first letter of every word
If the original Name profile property has the value set to “alex!”, this transformation would result in the creation of a new profile property called Name__transformed, with the value set to Alex.
Standardize
With the standardization transformation method, you can set rules to automatically replace specific profile property values.

To create a standardization rule:
- In the If value condition, select Contains or Equals.
The Contains operator requires the property value being replaced to contain the specified substring you enter for the If value. Note that the entire property value will be replaced, not just the substring matched. Contains only supports text values.
The Equals operator requires the existing property value to exactly match 1 of the values entered under If value. When it matches, the entire value is replaced with the Replace with value.
- Select the data type for the If value.
- Select up to 30 values to match in the If value condition. The dropdown suggests up to 512 existing values for the property. To match a value that is not listed, select Enter new value and enter it; this adds a match value to the rule, not a new value to your profiles.

First Name and Last Name can have suggested values. If a value is missing from the dropdown, select Enter new value to add it to the condition.
- In the Replace with condition, select the data type for the replacement value.
- Enter your desired replacement value in the Replace with condition.
For the List data type, enter a valid JSON array with square brackets and comma-separated values, such as [1,2,3] or ["A",1,true]. Use double quotes around text values and lowercase true or false for booleans.
You can create up to 50 standardization rules in a transformation. Rules run in order, and a later rule can replace an earlier rule’s result if it matches that result. Check your conditions to avoid unintended replacements. If no standardization rule matches, the value passes through unchanged.
- To add another condition, select + Add rule and enter its match and replacement values.
- Select Save when all your standardization rules are ready.
Example Standardize transformation
In this example, the Standardize transformation is being applied to the Country profile property using the standardization rules:
- If value contains America Replace with USA
- If value equals Can Replace with Canada
- If value equals “Canada” Replace with Canada
If the Country profile property has the value set to America, this transformation would result in the creation of a new profile property called Country__transformed with the value set to USA. If the value for the Country property was originally set to “Canada”, this would create the Country__transformed property with the value set to Canada.
Merge
The Merge transformation allows you to combine multiple custom profile properties into 1, allowing you to effectively use the data in segments and templates.
Transformations are applied in the following order:
- Merge
- Format
- Standardize
To create a merge rule:
- Select 2–10 profile properties to merge. To include another property, select + Add.
Klaviyo uses the first property in the list with a value. If that property is missing or blank on a profile, it checks the next property. For example, if Hair type is first, its value takes priority when it is available. The output property is called Hair type__transformed.

- Use the up and down arrows to change the priority of the properties.
You can combine up to 10 properties with a single Merge transformation. Note that once you save the transformation, you can no longer change the topmost priority. Instead, you can delete the transformation and create a new one.
- Select Save once your merge transformation is set up.
Example Merge transformation
In this example, the Merge transformation is being applied to the Birthday and Birthdate properties to combine into a single property called Birthday__transformed.

If 1 profile has Birthday set to 06/07/1998 and another has only Birthdate set to 06/04/2001, both get a new property called Birthday__transformed with their respective dates. Their original properties and values remain unchanged. If a profile has both properties, the first property in the merge list takes priority.
Pre-built transformations
There are 4 pre-built transformations you can quickly enable with the Transformation tool.
- Format first names
Capitalize the first name of profiles for consistency in your messaging (e.g., alex to Alex).

- Standardize country names
Standardize common country names so they all have the same value, allowing for consistency across similar profiles and easier segmentation (e.g., U.S. or USA to United States).

- Standardize U.S. state names
Standardize the values for all 50 states, allowing for consistency across similar profiles and easier segmentation (e.g., NY or New york to New York).

- Format birthdays
Format birthday properties for consistency in segmentation and messaging.

- Navigate to Data management > Transformation in the Advanced section and select Profile properties. If this is your first transformation, the pre-built options appear on the page. If you already have transformations, select Create to view them.

- Select a pre-built transformation to open the builder with its rules already defined. Review the rules and add or edit them based on your needs.

If the original property already has a Standardize or Format transformation, you cannot create another transformation of the same type for it. Edit the existing transformation instead.
- Select Save when the pre-built transformation is ready. The transformation is activated and appears in your transformation list.

Managing transformations
Once you have a data transformation created in Klaviyo, you’ll see it listed on the Transformations page with the following details:
- Profile property
The name of the original profile property that is being transformed. - New profile property name
The name of the transformed profile property. - Transformation method
The transformation method used. - Status
The status of the transformation (i.e., Active, In progress, Inactive). - Last edited
When the transformation was last created or edited.

You can have up to 30 transformations active at once.
When a new transformation is first created, its status is In progress. While in this status, the transformation is being applied in bulk to existing profiles. Once bulk transformation is complete, the status becomes Active. Any new profiles or updates to existing profiles will be transformed live.
From the menu next to each transformation, you can:
- Edit existing transformations
- Delete transformations
- Select Set to active to reactivate inactive Format or Standardize transformations.
To update or retransform a property, select Edit from the transformation’s menu, change its rules, and select Save. To delete a transformation, select Delete from the menu and confirm with Delete in the dialog.

Note that deleting a transformation will not delete already transformed properties saved under Property__transformed, but the transformation will no longer be applied to any new data.
If you lose access to the Data transformation feature because a trial ended or you are no longer using the Advanced KDP add-on:
- All transformations will be set to the Inactive state.
- Transformations will no longer apply to new data.
- Previously transformed data will continue to be available.
If you regain access to Advanced KDP, select Set to active in the menu for an inactive Format or Standardize transformation. To resume an inactive Merge transformation, note its source properties and priority order, then delete it and create a new transformation using those settings. Deleting it preserves the previously transformed property values.
Additional resources
- Understanding data types
Learn about the different options available for storing your data in Klaviyo, and how to use each one. Klaviyo allows you to harness the data collected about your customers to power data-driven marketing choices that will grow your brand. That being said, it's important to understand the data that's being pulled into your account.
- Profile properties reference
Learn about the difference between custom and Klaviyo properties, how to use them to track information about your subscribers, how to remove them, best practices, and more.