> ## Documentation Index
> Fetch the complete documentation index at: https://loops.so/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Send a preview of an email message

> Send a test preview of an email message to one or more addresses.

Send a test email message to one or more addresses. Accepted variable fields depend on the parent's type:

* **Campaign** accepts `contactProperties`.
* **Workflow** accepts `contactProperties` and `eventProperties`.
* **Transactional** accepts `dataVariables`.

Supplying a field the parent cannot reference results in a `400 Bad Request` error.

Each team can send up to 100 preview emails per day.


## OpenAPI

````yaml /openapi.json post /v1/email-messages/{emailMessageId}/preview
openapi: 3.1.0
info:
  title: Loops OpenAPI Spec
  description: This is the OpenAPI Spec for the [Loops API](https://loops.so/docs/api).
  version: 1.21.0
servers:
  - url: https://app.loops.so/api
security: []
tags:
  - name: API key
  - name: Audience segments
    description: View audience segments
  - name: Campaigns
    description: Create and manage email campaigns
  - name: Campaign groups
    description: Organize campaigns into groups
  - name: Components
    description: View email components
  - name: Configuration
    description: View configuration settings
  - name: Contacts
    description: Manage contacts in your audience
  - name: Contact properties
    description: Manage contact properties
  - name: Email messages
    description: Manage email message content for campaigns
  - name: Events
    description: Trigger workflows with events
  - name: Event patterns
    description: View workflow event patterns
  - name: Mailing lists
    description: View mailing lists
  - name: Themes
    description: View email themes
  - name: Transactional emails
    description: Create, manage, and send transactional emails
  - name: Transactional groups
    description: Organize transactional emails into groups
  - name: Uploads
    description: Upload image assets
  - name: Workflows
    description: View and mutate workflow graphs
  - name: Workflow nodes
    description: View and mutate workflow nodes
paths:
  /v1/email-messages/{emailMessageId}/preview:
    parameters:
      - name: emailMessageId
        in: path
        required: true
        description: The ID of the email message.
        schema:
          type: string
    post:
      tags:
        - Email messages
      summary: Send a preview of an email message
      description: >-
        Send a test preview of an email message to one or more addresses. The
        accepted variable fields depend on the parent's type - campaign previews
        accept `contactProperties`, workflow previews accept `contactProperties`
        and `eventProperties`, and transactional previews accept
        `dataVariables`. Supplying a field the parent cannot reference is
        rejected with 400.
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/EmailMessagePreviewRequest'
      responses:
        '200':
          description: Preview scheduled.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/EmailMessagePreviewResponse'
        '400':
          description: >-
            Invalid request body, or a variable field the parent cannot
            reference.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/EmailMessageFailureResponse'
        '401':
          description: Invalid API key or content API not enabled for this team.
        '404':
          description: Email message not found.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/EmailMessageFailureResponse'
        '405':
          description: Wrong HTTP request method.
        '429':
          description: The daily preview limit was reached.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/EmailMessageFailureResponse'
      security:
        - apiKey: []
components:
  schemas:
    EmailMessagePreviewRequest:
      type: object
      properties:
        emails:
          type: array
          minItems: 1
          items:
            type: string
          description: One or more addresses to send the preview to.
        contactProperties:
          type: object
          additionalProperties:
            type: string
          description: >-
            Contact property values to render. Accepted for campaign and
            workflow previews.
        eventProperties:
          type: object
          additionalProperties:
            type: string
          description: >-
            Event property values to render. Accepted for workflow previews
            only.
        dataVariables:
          type: object
          description: >-
            Transactional data variables to render. Accepted for transactional
            previews only.
      required:
        - emails
      additionalProperties: false
    EmailMessagePreviewResponse:
      type: object
      properties:
        id:
          type: string
          description: The ID of the email message the preview was sent for.
      required:
        - id
    EmailMessageFailureResponse:
      type: object
      properties:
        message:
          type: string
      required:
        - message
  securitySchemes:
    apiKey:
      type: http
      scheme: bearer

````

## Related topics

- [Transactional email API examples](/docs/api-reference/examples/transactional-emails.md)
- [Email messages](/docs/cli/email-messages.md)
- [Campaigns API examples](/docs/api-reference/examples/campaigns.md)
- [Send a transactional email](/docs/api-reference/send-transactional-email.md)
- [Create a campaign](/docs/api-reference/create-campaign.md)