Bytedance seedream 4.0 API | Pricing & Docs

bytedance/seedream-4-0/edit

Edit and fuse multiple images into high-quality results with strong prompt control, flexible resolutions, and consistent styling.

1. Get started

Use RunComfy's API to run bytedance/seedream-4-0/edit. For accepted inputs and outputs, see the model's schema.

curl --request POST \
  --url https://model-api.runcomfy.net/v1/models/bytedance/seedream-4-0/edit \
  --header "Content-Type: application/json" \
  --header "Authorization: Bearer <token>" \
  --data '{
    "prompt": "Turn this into a sunrise scene with warm golden light; keep the subject as is; add light morning fog and soft highlights; subtle reflections to add depth",
    "images": [
      "https://playgrounds-storage-public.runcomfy.net/tools/7007/media-files/usecase2-2-input.png"
    ]
  }'

2. Authentication

Set the YOUR_API_TOKEN environment variable with your API key (manage keys in your Profile) and include it on every request as a Bearer token via the Authorization header: Authorization: Bearer $YOUR_API_TOKEN.

3. API reference

Submit a request

Submit an asynchronous generation job and immediately receive a request_id plus URLs to check status, fetch results, and cancel.

curl --request POST \
  --url https://model-api.runcomfy.net/v1/models/bytedance/seedream-4-0/edit \
  --header "Content-Type: application/json" \
  --header "Authorization: Bearer <token>" \
  --data '{
    "prompt": "Turn this into a sunrise scene with warm golden light; keep the subject as is; add light morning fog and soft highlights; subtle reflections to add depth",
    "images": [
      "https://playgrounds-storage-public.runcomfy.net/tools/7007/media-files/usecase2-2-input.png"
    ]
  }'

Monitor request status

Fetch the current state for a request_id ("in_queue", "in_progress", "completed", or "cancelled").

curl --request GET \
  --url https://model-api.runcomfy.net/v1/requests/{request_id}/status \
  --header "Authorization: Bearer <token>"

Retrieve request results

Retrieve the final outputs and metadata for the given request_id; if the job is not complete, the response returns the current state so you can continue polling.

curl --request GET \
  --url https://model-api.runcomfy.net/v1/requests/{request_id}/result \
  --header "Authorization: Bearer <token>"

Cancel a request

Cancel a queued job by request_id, in-progress jobs cannot be cancelled.

curl --request POST \
  --url https://model-api.runcomfy.net/v1/requests/{request_id}/cancel \
  --header "Authorization: Bearer <token>"

4. File inputs

Hosted file (URL)

Provide a publicly reachable HTTPS URL. Ensure the host allows server‑side fetches (no login/cookies required) and isn't rate‑limited or blocking bots. Recommended limits: images ≤ 50 MB (~4K), videos ≤ 100 MB (~2–5 min @ 720p). Prefer stable or pre‑signed URLs for private assets.

5. Schema

Input schema

{
  "type": "object",
  "title": "Input",
  "required": [
    "prompt",
    "images"
  ],
  "properties": {
    "prompt": {
      "title": "Prompt",
      "description": "The recommended length is no more than 600 English words. If the prompt is too long, the information may become scattered. The model might ignore details and only concentrate on the main points, resulting in a image with missing elements.",
      "type": "string",
      "default": "Turn this into a sunrise scene with warm golden light; keep the subject as is; add light morning fog and soft highlights; subtle reflections to add depth"
    },
    "images": {
      "title": "Images",
      "description": "Upload 1~10 images. The format must be jpeg or png",
      "type": "array",
      "items": {
        "type": "string",
        "format": "image_uri"
      },
      "validations": [
        {
          "validation_rule": "file_size_mb<",
          "validation_value": 10,
          "validation_error": "File size must be less than 10 MB."
        },
        {
          "validation_rule": "width/height>",
          "validation_value": 0.33,
          "validation_error": "The aspect ratio range should be 1:3 to 3:1."
        },
        {
          "validation_rule": "width/height<",
          "validation_value": 3,
          "validation_error": "The aspect ratio range should be 1:3 to 3:1."
        },
        {
          "validation_rule": "width_pixels>",
          "validation_value": 14,
          "validation_error": "The uploaded image width and height must exceed 14 pixels."
        },
        {
          "validation_rule": "height_pixels>",
          "validation_value": 14,
          "validation_error": "The uploaded image width and height must exceed 14 pixels."
        }
      ],
      "maxItems": 10,
      "minItems": 1,
      "default": [
        "https://playgrounds-storage-public.runcomfy.net/tools/7007/media-files/usecase2-2-input.png"
      ]
    },
    "resolution": {
      "title": "Resolution",
      "description": "",
      "type": "string",
      "enum": [
        "1K",
        "2K",
        "4K",
        "2048x2048 (1:1)",
        "2304x1728 (4:3)",
        "1728x2304 (3:4)",
        "2560x1440 (16:9)",
        "1440x2560 (9:16)",
        "2496x1664 (3:2)",
        "1664x2496 (2:3)",
        "3024x1296 (21:9)"
      ],
      "default": "2048x2048 (1:1)"
    }
  }
}

Output schema

{
  "output": {
    "type": "object",
    "properties": {
      "image": {
        "type": "string",
        "format": "uri",
        "description": "single image URL"
      },
      "video": {
        "type": "string",
        "format": "uri",
        "description": "single video URL"
      },
      "images": {
        "type": "array",
        "description": "multiple image URLs",
        "items": { "type": "string", "format": "uri" }
      },
      "videos": {
        "type": "array",
        "description": "multiple video URLs",
        "items": { "type": "string", "format": "uri" }
      }
    }
  }
}

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