> For the complete documentation index, see [llms.txt](/llms.txt).
> A full single-fetch corpus is available at [llms-full.txt](/llms-full.txt).
---
title: "Preview deduplication"
description: "Preview which draft items would be removed by deduplication, without changing anything."
method: "POST"
endpoint: "/api/v1/projects/:projectId/datasets/:id/dedup/preview"
order: 13
group: "Deduplication"
last_verified: 2026-07-27
---

<ApiEndpoint method="POST" endpoint="/api/v1/projects/:projectId/datasets/:id/dedup/preview" description="Preview which draft items would be removed by deduplication, without changing anything.">
  <section>
    #### Response
    ```json {{ title: 'Response' }}
    {
      "success": true,
      "message": "Preview generated",
      "data": {
        "dataset_id": "1a2b3c4d-...",
        "duplicate_count": 6,
        "scanned_count": 214,
        "duplicate_groups": [
          {
            "fingerprint": "b2c3d4e5f6...",
            "items": [
              { "id": "9a8b7c6d-...", "created_at": 1732636800000 },
              { "id": "8b7c6d5e-...", "created_at": 1740000000000 }
            ]
          }
        ]
      }
    }
    ```
  </section>
</ApiEndpoint>