seedance-2.0-fast API

Use the exact model ID seedance-2.0-fast. The model field must match this page exactly.

Authentication and endpoint

Use a Modelflare API key with https://modelflare.dev/v1. The gateway entry point is POST /v1/videos.

HTTP

Authorization: Bearer YOUR_MODELFLARE_API_KEY

Create a task

bash

curl https://modelflare.dev/v1/videos \
  -H "Authorization: Bearer YOUR_MODELFLARE_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "seedance-2.0-fast",
    "content": [{"type": "text", "text": "A white cat runs through a neon-lit street in the rain, cinematic tracking shot"}],
    "resolution": "720p",
    "duration": 5,
    "generate_audio": false
  }'

Poll and download

Save the task ID. Poll GET /v1/videos/{task_id} and download with GET /v1/videos/{task_id}/content. Result URLs may expire, so transfer the file promptly.

bash

curl https://modelflare.dev/v1/videos/TASK_ID \
  -H "Authorization: Bearer YOUR_MODELFLARE_API_KEY"

Request notes

Seedance uses content[] for text, frames, and reference media; the separate Seedance asset management contract is documented independently.

Request parameters

Seedance uses one asynchronous multimodal envelope. Put text and media in content[]; media roles select first/last-frame or reference workflows.

Field	Required	Notes
model	Yes	seedance-2.0-fast
content[]	Yes	text, image_url, video_url, and audio_url; use role to identify media purpose
resolution	No	480p / 720p (default 720p)
ratio	No	21:9 / 16:9 / 4:3 / 1:1 / 3:4 / 9:16 / adaptive
duration	No	-1 for automatic timing, or 4–15 seconds
generate_audio	No	Generate synchronized dialogue, effects, and background audio
tools	No	Use web_search only where the official model page supports it
watermark	No	Whether to add a watermark

Input and output limits

This model supports 480p and 720p. Use -1 for automatic timing or choose 4–15 seconds; the frame rate is fixed at 24fps. Multimodal references allow up to nine images, three videos, and three audio clips; audio cannot be used alone, so a request needs at least one reference image or video. Mark media with role values in content[]; first-frame, editing, and extension workflows are mutually exclusive. This model does not accept frames, camera_fixed, output_format, or omni_reference_task_type.

Documented workflow examples

The Seedance 2.0 series supports text-to-video, first/first-and-last frames, multimodal references, editing, extension, and web search for text-to-video. Order media as text, image, video, then audio.

Multimodal reference

bash

curl https://modelflare.dev/v1/videos \
  -H "Authorization: Bearer YOUR_MODELFLARE_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "seedance-2.0-fast",
    "content": [
      {"type": "text", "text": "@image1 performs the movement from @video1, paced to @audio1"},
      {"type": "image_url", "image_url": {"url": "https://example.com/character.jpg"}, "role": "reference_image"},
      {"type": "video_url", "video_url": {"url": "https://example.com/motion.mp4"}, "role": "reference_video"},
      {"type": "audio_url", "audio_url": {"url": "https://example.com/music.mp3"}, "role": "reference_audio"}
    ],
    "generate_audio": true, "ratio": "16:9", "duration": 11
  }'

Video editing and web search

bash

curl https://modelflare.dev/v1/videos \
  -H "Authorization: Bearer YOUR_MODELFLARE_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "seedance-2.0-fast", "content": [{"type": "text", "text": "Macro shot of cherry blossoms in spring"}],
    "generate_audio": true, "ratio": "16:9", "duration": 11,
    "tools": [{"type": "web_search"}]
  }'

Errors and failed tasks

Invalid model parameters return a 4xx with a request ID. An asynchronous task can also enter failed after creation succeeds; use error_code and error_message from the poll response as the final task reason. Do not retry the same request with a different JSON shape.

Supported scope

This page covers Modelflare model generation and editing calls. Search or map enrichment, voice management, and element-library management are resource APIs outside this public model-call surface and are not required request fields.

Pricing and billing

This model uses token-based billing. See the model pricing page for the current customer price, reference list price, and complete specification.

Note

This page documents Modelflare’s public interface; the fields and limits shown here are the current contract.