> ## Documentation Index
> Fetch the complete documentation index at: https://docs.modellix.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Seedance 2.0 Fast T2V

> [Core Function] Seedance 2.0 Fast T2V is the faster text-to-video variant. [Strengths] Supports 480p/720p, 24 fps, 4-15s MP4 output. [Routing] Use when speed is preferred over maximum resolution.



## OpenAPI

````yaml /model-api/bytedance/bytedance-t2v.json post /bytedance/seedance-2.0-fast-t2v
openapi: 3.1.0
info:
  description: The text-to-video models API from ByteDance.
  version: 1.0.0
  contact:
    name: Modellix Support
    email: support@modellix.ai
  title: ByteDance Text-to-Video Models API
servers:
  - url: https://api.modellix.ai/api/v1
    description: The text-to-video models API from ByteDance.
security:
  - bearerAuth: []
paths:
  /bytedance/seedance-2.0-fast-t2v:
    post:
      summary: Seedance 2.0 Fast T2V
      description: >-
        [Core Function] Seedance 2.0 Fast T2V is the faster text-to-video
        variant. [Strengths] Supports 480p/720p, 24 fps, 4-15s MP4 output.
        [Routing] Use when speed is preferred over maximum resolution.
      operationId: seedance20FastT2vAsync
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/Seedance20FastT2vRequest'
      responses:
        '200':
          description: Task submitted successfully
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/AsyncTaskResponse'
components:
  schemas:
    Seedance20FastT2vRequest:
      type: object
      required:
        - prompt
      description: >-
        Seedance 2.0 text-to-video request. Required: `prompt` only. Text-only
        input — images, video, and audio parameters are not supported on T2V
        endpoints.
      properties:
        prompt:
          type: string
          minLength: 1
          maxLength: 10000
          description: >-
            Required. Text prompt describing the desired video. Maximum 10000
            characters. Do not pass images, video, or audio on T2V. Recommended
            prompt length: under 1000 words.
        ratio:
          type: string
          enum:
            - '21:9'
            - '16:9'
            - '4:3'
            - '1:1'
            - '3:4'
            - '9:16'
          default: '16:9'
          description: Aspect ratio of the generated video.
        resolution:
          type: string
          enum:
            - 480p
            - 720p
          default: 720p
          description: Output resolution of the video.
        duration:
          type: integer
          enum:
            - 4
            - 5
            - 6
            - 7
            - 8
            - 9
            - 10
            - 11
            - 12
            - 13
            - 14
            - 15
          default: 5
          description: Video duration in seconds (4-15 seconds).
        seed:
          type: integer
          minimum: -1
          maximum: 4294967295
          default: -1
          description: Random seed for reproducible generation. Use -1 for random.
        camera_fixed:
          type: boolean
          default: false
          description: Whether to keep the camera fixed during generation.
        generate_audio:
          type: boolean
          default: true
          description: Whether to generate audio.
        execution_expires_after:
          type: integer
          default: 172800
          minimum: 3600
          maximum: 259200
          description: Task expiration time in seconds.
        return_last_frame:
          type: boolean
          default: false
          description: Whether to return the last frame of the generated video.
    AsyncTaskResponse:
      type: object
      required:
        - code
        - message
        - data
      properties:
        code:
          type: integer
          description: Response code, 0 indicates success
          example: 0
        message:
          type: string
          description: Response message
          example: success
        data:
          type: object
          required:
            - status
            - task_id
            - model_id
          properties:
            status:
              type: string
              enum:
                - pending
                - processing
              description: Task status
              example: pending
            task_id:
              type: string
              description: Unique task identifier
              example: task-abc123
            model_id:
              type: string
              description: Model ID
              example: model-123
            get_result:
              type: object
              description: API information to query the task result
              properties:
                method:
                  type: string
                  description: HTTP method
                  example: GET
                url:
                  type: string
                  description: Full URL to query the task result
                  example: https://api.modellix.ai/api/v1/tasks/task-abc123
          description: Detailed data about the submitted asynchronous task.
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      description: 'API Key authentication. Format: `Bearer YOUR_API_KEY`.'

````