Upload media from file

curl -X POST "https://upload.postsyncer.com/api/v1/media/upload/file" \
  -H "Authorization: Bearer YOUR_API_TOKEN" \
  -F "workspace_id=12" \
  -F "file=@/path/to/photo.jpg"

{
  "media": {
    "id": 1842,
    "name": "photo.jpg",
    "url": "https://…",
    "mime_type": "image/jpeg",
    "size": 240512,
    "is_processing": false,
    "type": "image",
    "ai_generated_id": null,
    "is_reference": false,
    "progress": 100,
    "alt": null
  }
}

POST

api

media

upload

file

curl -X POST "https://upload.postsyncer.com/api/v1/media/upload/file" \
  -H "Authorization: Bearer YOUR_API_TOKEN" \
  -F "workspace_id=12" \
  -F "file=@/path/to/photo.jpg"

{
  "media": {
    "id": 1842,
    "name": "photo.jpg",
    "url": "https://…",
    "mime_type": "image/jpeg",
    "size": 240512,
    "is_processing": false,
    "type": "image",
    "ai_generated_id": null,
    "is_reference": false,
    "progress": 100,
    "alt": null
  }
}

Do not call this on the standard API host. Use https://upload.postsyncer.com/api/v1/media/upload/file, not https://postsyncer.com/api/v1/.... Same Bearer token as every other endpoint; only the hostname changes so large multipart uploads hit dedicated infrastructure (overview).

Upload one image, video, or document with multipart/form-data. Fields:

workspace_id (required) - workspace that will own the file
file (required) - the binary upload
folder_id (optional) - media library folder in that workspace

The API reads the MIME type from the file (you do not send mimeType). Allowed types are the same as in the app:

Images - JPEG, PNG, GIF, WebP
Video - MP4, MOV/QuickTime, MKV, WebM
Documents - PDF, DOC, DOCX, PPT, PPTX

Maximum size per request is 500MB (same as the in-app standard upload).

Documents publish to LinkedIn only. A PDF, DOC, DOCX, PPT, or PPTX attachment becomes a LinkedIn document post (the swipeable carousel). LinkedIn accepts one document per post, and the document must be the first item in content[].media - see Media overview. Other platforms ignore document attachments. Documents are not accepted in comment media.

Response 201: { "media": { "id", "url", "mime_type", ... } } - use media.id in Create post content[].media. Do not use this endpoint for URL import - use Import from URL.

Request

integer

required

Workspace that will own the file

file

required

Image, video, or document file (documents are LinkedIn-only)

integer

Optional media library folder id belonging to workspace_id

Example

curl -X POST "https://upload.postsyncer.com/api/v1/media/upload/file" \
  -H "Authorization: Bearer YOUR_API_TOKEN" \
  -F "workspace_id=12" \
  -F "file=@/path/to/photo.jpg"

{
  "media": {
    "id": 1842,
    "name": "photo.jpg",
    "url": "https://…",
    "mime_type": "image/jpeg",
    "size": 240512,
    "is_processing": false,
    "type": "image",
    "ai_generated_id": null,
    "is_reference": false,
    "progress": 100,
    "alt": null
  }
}

Use on a post:

"content": [{ "text": "Hello", "media": [1842] }]

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Guides

MCP

API reference

Upload media from file