---
title: "POST /v1/workspaces/{workspaceId}/templates/preview"
method: POST
path: "/v1/workspaces/{workspaceId}/templates/preview"
---

# POST /v1/workspaces/{workspaceId}/templates/preview

`POST /v1/workspaces/{workspaceId}/templates/preview`

## Request

- Base URL: `https://api.bangermail.com`
- URL: `https://api.bangermail.com/v1/workspaces/{workspaceId}/templates/preview`
- Auth: HTTP bearer

Render unsaved design input with sample or audience values and report placeholder gaps.

## Request body

- object
  - `subject` string
  - `body_text` string
  - `body_html` string
  - `content` object
  - `audience` CampaignAudience: Select all subscribed contacts or at least one nonempty contact_ids, list_ids, or segment_ids list.
    - `all_subscribed` boolean
    - `contact_ids` string[]
    - `list_ids` string[]
    - `segment_ids` string[]
  - `sample_email` string: An existing contact email. Unknown addresses return sample_recipient_not_found. Omit to use sample or audience values.

## Response `200`

Successful response.

- object
  - `data` EmailDesignPreview, required
    - `subject` string, required
    - `body_text` string, required
    - `body_html` string
    - `font_rendering` EmailFontReport[], required
      - `stack` string, required
      - `font` string, required
      - `web_font` boolean, required
      - `clients` object[], required
        - `client` string, required
        - `label` string, required
        - `font` string, required
        - `web_font` boolean, required
        - `fallback` boolean, required
    - `sample_recipient` object, nullable, required
      - `email` string, required
      - `display_name` string, nullable, required
    - `required_variables` string[], required
    - `effective_slots` TemplateSlot[], required
      - `key` string, required
      - `label` string
      - `type` 'text' | 'paragraph' | 'url' | 'image'
      - `help` string
    - `audience_count` integer
    - `gaps` object[]
      - `variable` string, required
      - `missing_count` integer, required
      - `sample_emails` string[], required

## Other responses

- `400`: sample_email is empty or another preview parameter is invalid.
- `404`: The requested resource does not exist in this workspace.

---

[API](https://skmtc.dev/bangermail/apis/banger-api.md) · [All operations](https://skmtc.dev/bangermail/apis/banger-api/llms.txt) · [OpenAPI document](https://skmtc.dev/bangermail/apis/banger-api/revisions/a149909267f9?raw)