---
title: "What switching format would do"
method: GET
path: "/dashboards/{dashboard_id}/format-preview"
tags: ["Dashboard v3"]
---

# What switching format would do

`GET /dashboards/{dashboard_id}/format-preview`

## Request

- Base URL: `https://app.mammoth.io/api/v2`
- URL: `https://app.mammoth.io/api/v2/dashboards/{dashboard_id}/format-preview`
- Auth: one of:
  - HTTP bearer
  - API key in header `X-API-KEY` and API key in header `X-API-SECRET` and API key in header `X-WORKSPACE-ID`

The format dialog's ledger: what carries over unchanged, what the floor would add for the new style, and what the target format cannot display. Computed by dry-running the REAL floor on a copy — never by re-describing its rules in a second place, which drifts out of truth on the first rule change. Side-effect free: nothing is persisted, so the dialog can be opened and dismissed freely (mirrors the BI-export pre-flight).

## Path parameters

- `dashboard_id` integer, required

## Query parameters

- `style` string, required

## Response `200`

What a format switch would do

- FormatPreviewResponse
  - `style` string, required: The style being previewed
  - `charts_carried` integer: Chart tiles that carry over unchanged
  - `kpis_carried` integer: KPI cards that carry over
  - `filters_carried` integer: Declared filters that carry over
  - `pages_after` integer: Pages the board would have after the switch
  - `filters_added` integer: Filter-sidebar entries the floor would add
  - `pages_added` string[]: Titles of content pages the floor would add
  - `cover_added` boolean: A document cover would be prepended
  - `qa_added` boolean: A Q&A tab would be added
  - `not_shown` FormatPreviewNotShown[]: Things the target format cannot display. NOT losses — the canvas keeps them and a switch back restores them — which is why the wording is 'not shown' rather than 'dropped'.
    - `what` string, required: What the target format will not display
    - `count` integer, required: How many of them
    - `reason` string, required: Why, in the reader's terms

## Other responses

- `400`: Bad request syntax or unsupported method
- `403`: Request forbidden -- authorization will not help

---

[API](https://skmtc.dev/mammoth/apis/mammoth-analytics.md) · [All operations](https://skmtc.dev/mammoth/apis/mammoth-analytics/llms.txt) · [OpenAPI document](https://skmtc.dev/mammoth/apis/mammoth-analytics/revisions/5dfd1c296ded?raw)