What is segmentation?

Segmentation helps you create dynamic groups of contacts based on behaviors, properties, and subscription data. With the updated Segmentation tool and the new Mailjet AI Assistant, you can now build precise, targeted segments faster and without needing technical knowledge or complex logic rules.

This guide explains how to create, refine, and manage segments using both the traditional logic builder and the new AI-powered natural language input.

Segmentation allows you to filter your audience dynamically, sending relevant content to those most interested. Here are some use cases:

• Re-engage inactive subscribers (e.g., those who haven’t opened emails in 60 days).
• Welcome new subscribers with a promo code.
• Tailor campaigns based on demographics such as location, age, or preferences.
• Target users based on topics selected during signup.

What’s New in the Updated Segmentation Experience

👉Enhanced UI and Logic Builder

All existing segmentation capabilities remain available, but with improved layout, faster performance, and clearer rule creation.

👉AI Assistant for Segmentation

A new generative AI model assists you in defining your segmentation criteria using natural language. The system translates your prompt into a structured rule set that you can review, refine, and save.

👉Improved Rule Transparency

After generating a segment via AI, users can inspect the translated conditions in the rule builder before applying them.

👉Guided Error Handling

Ambiguous or unsupported prompts trigger helpful clarifying questions or suggested rephrasing.

👉Future-Ready Foundation

This update prepares Mailjet for additional AI-powered personalization and automation features.

Before you start

1. Review contact properties: Ensure your contact properties are set up properly. For help, refer to the FAQ: How to create & manage contact properties.
2. Enable tracking: Confirm that open and click tracking are activated in your account settings.

Access your segments

From the Dashboard, select Contacts → Segmentation.

• If you’ve used segmentation before, you’ll see a list of your existing segments, which you can manage or edit.
• If you’re new to segmentation, the My Segments page will appear empty. Click Create a Segment to begin.

How the AI Assistant Works

Step 1 — Enter a Natural Language Prompt

Open the AI Assistant by clicking the magic wand icon in the top-right corner, then describe the audience you want to target. 

For example:

• Contacts who opened an email in the last 30 days and are in Germany

• Inactive users from France who haven’t opened any campaign in 6 months

• Contacts tagged VIP who signed up via the Black Friday campaign

• Contacts who clicked any link in the March newsletter and joined in the last 90 days

Step 2 — AI Translates the Request

The Assistant converts your request into structured segmentation rules.

Step 3 — Review the Generated Rules

The visual logic builder displays the proposed filters:

• You can edit, add, or remove conditions.

• Nothing is saved until you confirm the segment.

Step 4 — Handle Ambiguities

If your request is unclear, the Assistant may:

• Ask follow-up questions

• Suggest alternative wording

• Display a fallback rule with note indicators

Step 5 — Save and view the Segment

Save the newly created segment, then preview it to test your criteria and confirm the results.

Segmentation options

Mailjet’s segmentation engine allows you to combine multiple filter types to build precise and dynamic target audiences. All filters can be mixed using AND/OR conditions and refined through nested groups.

Below is the updated list of available filters in the new segmentation experience.

Contact Activities 

These filters allow you to segment contacts based on how they engage with your campaigns.

👉Specific Campaign Activity

These filters target contacts based on actions within a specific campaign.

• Clicked in the campaign

• Not clicked the campaign

• Opened the campaign

• Not opened the campaign

👉Historical Activity Across All Campaigns

These filters apply to engagement across all campaigns within a defined timeframe.

Clicks

• Clicked in a campaign in the last X days

• Not clicked a campaign in the last X days

• Clicked in the last X days

• Not clicked in the last X days

Opens

• Opened a campaign in the last X days

• Not opened a campaign in the last X days

• Opened in the last X days

• Not opened in the last X days

Contact List Subscription 

These filters allow you to build segments based on how contacts subscribe or interact with your lists.

• Is subscribed to list

• Has not subscribed to list

• Subscribed in the last X days

• Has not subscribed in the last X days

These options help marketers target new subscribers, inactive subscribers, or contacts who are not part of a specific list.

Contact Properties 

Contact property-based segmentation allows you to filter your audience using data fields such as age, location, or membership type. The type of contact property determines the available filter options, with different operators provided for strings, numbers, dates, and boolean values. For example, you might filter contacts based on their city, age, or whether they are subscribed to your VIP program.

Common examples include:

• email

• first_name

• last_name

• country

• city

• signup_source

• tags/labels (such as VIP, Promo2025, BlackFriday)

• any custom property created in the Contacts section

Below, you’ll find definitions of each contact property type and the operators available for creating segments:

👉 String properties

A string property consists of text or characters, such as "City" or "First Name." You can filter string properties using the following operators:

• Is: Matches the exact value entered. Case sensitive. (Example: City is "Paris")
• Is not: Excludes the exact value entered. Case sensitive. (Example: City is not "London")
• Is provided: Includes contacts where the property is not blank.
• Is not provided: Includes contacts where the property is blank.
• Starts with: Matches the beginning of the property value. (Example: State starts with "New")
• Does not start with: Excludes contacts whose property value begins with the value you enter. (Example: State does not start with “New”)
• Ends with: Matches the end of the property value. (Example: City ends with "ville")
• Does not end with: Excludes contacts whose property value ends with the value you enter. (Example: City does not end with “ville”)
• Contains: Matches any part of the property value. (Example: Plan contains "Premium")
• Does not contain: Excludes matches based on any part of the property value. (Example: Plan does not contain "Basic"). 

👉 Integer or Decimal properties

An integer property represents whole numbers, such as "Age" or "Purchase Count," while a decimal property allows numeric values with decimal points, such as "Order Value" (e.g., 50.99). You can filter these properties using the following operators:

• Is: Matches an exact number. (Example: Age equals 30)
• Is not: Excludes an exact number. (Example: Age does not equal 25)
• Is less than: Includes values below the specified number. (Example: Age is less than 18)
• Is less than or equal to: Includes values at or below the specified number. (Example: Age is less than or equal to 40)
• Is greater than: Includes values above the specified number. (Example: Age is greater than 50)
• Is greater than or equal to: Includes values at or above the specified number. (Example: Age is greater than or equal to 20)
• Is between: Includes values within a range. (Example: Age is between 25 and 35)
• Is provided: Includes contacts where the property has a numeric value.
• Is not provided: Includes contacts where the property is blank. 

👉 Date properties

A date property represents a specific calendar date, such as a subscription date or birthday. You can filter date properties using these operators:

• Is before: Includes dates earlier than the specified date. (Example: Join Date is before 01-01-2023)
• Is after: Includes dates later than the specified date. (Example: Join Date is after 12-31-2022)
• Is: Matches the exact date. (Example: Join Date is 02-14-2023)
• Is not: Excludes the specified date. (Example: Join Date is not 03-01-2023)
• Is today: Matches the current date.
• Is between: Includes dates within a range. (Example: Join Date is between 01-01-2023 and 01-31-2023)
• Is not between: Excludes dates that fall within the specified range. Contacts are included only if their date is before the start date or after the end date. (Example: Join Date is not between 01-01-2023 and 01-31-2023)
• Is in the next [days/months]: Includes dates in the future. (Example: Birthday is in the next 3 weeks)
• Is in the last [days/months]: Includes dates in the past. (Example: Join Date is in the last 12 days)
• Is not in the next [days/months]: Excludes future dates. (Example: Renewal Date is not in the next 6 months)
• Is not in the last [days/months]: Excludes past dates. (Example: Anniversary is not in the last year)
• Has anniversary on: Matches the day and month of the property, ignoring the year. (Example: Birthday has anniversary on 03-15)
• Is provided: Includes contacts where the property has a date value.
• Is not provided: Includes contacts where the property is blank. 

👉 Boolean properties

A boolean property has two possible values, such as true/false or 0/1. For example, a "VIP" field might indicate whether a contact is a priority user. You can filter boolean properties using the following operators:

• Is true: Includes contacts where the property is true. (Example: VIP is true)
• Is false: Includes contacts where the property is false. (Example: Subscribed is false) 

Creating a Segment (Step-by-Step)

👉 Option A — Using the AI Assistant

1. Navigate to Segmentation.

2. Select Create a Segment.

3. Choose the AI Assistant. 
   

4. Type your description (e.g., “Users in France who haven't opened any email in 6 months”).

5. Review the generated rules in the logic builder.

6. Adjust conditions if needed.

7. Save your segment.

8. Preview your segment (calculate)
   You can test your segment by applying it to any contact list. From the segment section, select a contact list and click ‘Calculate’.
   

   If a contact property has no value, that contact will not be included in the resulting segment. For example, if the city field is blank for a contact, that contact will not be included in the segmented list.

👉 Option B — Using the Logic Builder Manually

1. Navigate to Segmentation.

2. Select Create a Segment.

3. Add filters based on activity, lists, or properties.

4. Combine rules using AND/OR logic.
   

5. Save your segment.

6. Preview your segment (calculate)
   You can test your segment by applying it to any contact list. From the segment section, select a contact list and click ‘Calculate’.
   

   If a contact property has no value, that contact will not be included in the resulting segment. For example, if the city field is blank for a contact, that contact will not be included in the segmented list.

Understanding Rules, Groups, and AND/OR Logic in Segmentation

The segmentation builder allows you to create precise and dynamic audience definitions by combining filters using Rules, Groups, and Boolean logic (AND / OR). Understanding these three elements is essential for building correct and effective segments.

1. What is a Rule?

A Rule is a single condition that must be met for a contact to match your segment.

Examples of rules:

• Opened the campaign → Winter Newsletter

• city → Is → Paris

• language → Is → EN

• favorite_color → Is → Red

Each row in the builder represents one rule.

When to use “+ Rule”

You add a new Rule when you want to include another condition at the same logical level as the existing rules.

For example, adding:

• city Is Paris

• city Is London

Inside the same group means both rules are evaluated using the group’s logic (AND or OR).

2. What is a Group?

A Group is a container for multiple rules that are evaluated together under a single AND or OR operator.

Groups behave like parentheses in mathematics or programming logic.

Example

A group like this:

means:
Contacts who live either in Paris OR in London.

Groups allow you to create advanced logic, such as:

• A set of properties that must all be true (AND group)

• Any one of several options (OR group)

• A combination of both (nested groups)

When to use “+ Group”

You add a Group when you want to:

• Combine several rules under a single logic operator

• Create nested logic like “A AND (B OR C)”

• Organize complex conditions clearly

3. Understanding AND / OR Logic

👉 AND = All conditions must be true

If your top-level group uses AND, the contact must satisfy every rule in that group.

Example:

The contact must have opened the campaign and must live in Paris.

👉 OR = At least one condition must be true

If a group uses OR, the contact only needs to match one of the rules inside the group.

Example:

The contact qualifies if they speak either English OR French.

4. Combining AND and OR (Nested Logic)

The real power of segmentation comes from mixing groups.

Example:

In this example, the contact must:

1. Have opened the Winter Newsletter

2. And satisfy ONE of the rules in the nested group:

   • City = Paris

   • City = London

Preview Your Segment

Verify who will be included before you send.

Steps

1. Go to My segments and click on the segment name you want to preview.
   

2. Select a contact list.

3. Click Calculate.
   

What you’ll see

• A count of matching contacts for the selected list.

• A sample of 10 contacts that meet the conditions. If your segment uses contact properties, those property values are shown for each sampled contact.
  

Apply a Segment to your Campaign

Target the right audience before you hit send.

Steps

1. Go to Campaigns and create a new campaign.

2. Select your contact list.

3. Under audience options, choose Only send to a segment.

4. Open the dropdown:

   • Use an existing segment, or

   • Create a new segment (the builder expands so you can add filters and test against the selected list).

5. Click Calculate number of contacts to see how many recipients match.
   

6. If the count looks off, adjust your filters or list, then recalculate.

7. Continue designing your campaign and send as usual.

My Segments Page

You can manage all your segments in one place.

Go to Contacts → Segmentation. The My segments page lists your segments.

What you can do here

• Create new segments

• Edit existing segments

• Duplicate a segment as a starting point

• Delete segments you no longer need

👉 Edit a segment

1. In My segments, click on the cogwheel for the segment.

2. Choose Edit.

3. Rename the segment, remove filters (click X), or add new filters.

4. Click Save changes.
   

Tip: After edits, use Calculate to confirm the audience count.

👉 Duplicate a segment

1. Click on the Cogwheel, select Duplicate.

2. You’ll land on Edit segment for the copy—adjust the name and filters as needed.

3. Click Save.
   

👉 Delete a segment

1. Click on the Cogwheel, choose Delete.
   

2. Enter DELETE in the confirmation field, then confirm the action.