FLUX 3 Video

Use flux-3-video to create video output. This page contains the complete request needed for this model.

Model facts

Property	Value
Model ID	`flux-3-video`
Endpoint	`POST /api/v1/generation/create`
Output	Video
Modes	text-to-video, image-to-video, video reference
Pricing	View current pricing

Minimal request


curl -X POST https://api.api-stock.com/api/v1/generation/create \
  -H "Authorization: Bearer $API_STOCK_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "model": "flux-3-video",
  "input": {
    "prompt": "A cinematic scene with soft natural light"
  }
}'

The create response contains a task ID:


{
  "code": 200,
  "data": {
    "taskId": "019ca881-9503-7270-a560-f00fc2b15785",
    "status": "not_started",
    "createdAt": "2026-08-22T12:00:00.000Z"
  }
}

Parameters

Parameters belong inside the top-level input object. Unknown fields are rejected.

Parameter	Type	Required	Default	Description
`prompt`	string	Yes	—	Scene description: subject, action, camera movement, dialogue and sound
`resolution`	“720p” \| “1080p”	No	`"720p"`	Video resolution (affects pricing). Draft mode supports 720p only
`duration`	number	No	`5`	Video duration in seconds (5-20). Billed per second min 5, max 20
`aspectRatio`	“auto” \| “21:9” \| “2:1” \| “16:9” \| “4:3” \| “1:1” \| “3:4” \| “9:16”	No	`"auto"`	Video aspect ratio. `auto` lets the model choose from the prompt and input frames
`imageUrls`	string[]	No	—	Keyframes for image-to-video, in playback order. One image is the start frame, two are start + end, three or more are spread evenly across the clip
`videoUrl`	string	No	—	Source video (mp4) to continue. Continuation is billed at a higher per-second rate and cannot be combined with imageUrls
`draft`	boolean	No	`false`	Draft mode: a fast, low-quality 720p preview at about a third of the price
`safetyTolerance`	number	No	`2`	Moderation tolerance from 0 (strictest) to 4 (most permissive) min 0, max 4

Modes

Minimal generation


{
  "model": "flux-3-video",
  "input": {
    "prompt": "A cinematic scene with soft natural light"
  }
}

With image urls


{
  "model": "flux-3-video",
  "input": {
    "prompt": "A cinematic scene with soft natural light",
    "imageUrls": [
      "https://example.com/input.jpg"
    ]
  }
}

With video url


{
  "model": "flux-3-video",
  "input": {
    "prompt": "A cinematic scene with soft natural light",
    "videoUrl": "https://example.com/input.mp4"
  }
}

Constraints

resolution: allowed: 720p, 1080p.
duration: minimum 5; maximum 20.
aspectRatio: allowed: auto, 21:9, 2:1, 16:9, 4:3, 1:1, 3:4, 9:16.
safetyTolerance: minimum 0; maximum 4.

Invalid types, unsupported enum values, out-of-range numbers, and missing required fields return HTTP 400 with error.code: "invalid_input". Correct the request rather than retrying it unchanged.

Result

Poll the task or provide a top-level webhook URL in the create request:


curl https://api.api-stock.com/api/v1/task/status/$TASK_ID \
  -H "Authorization: Bearer $API_STOCK_KEY"

A successful media task returns one or more files:


{
  "code": 200,
  "data": {
    "taskId": "019ca881-9503-7270-a560-f00fc2b15785",
    "status": "finished",
    "files": [
      {
        "fileUrl": "https://s3.api-stock.com/result.mp4",
        "fileType": "video"
      }
    ],
    "createdTime": "2026-08-22T12:00:00.000Z"
  }
}

See Tasks and webhooks for terminal statuses, retries and webhook delivery.