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Documentation Index

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Pricing: $0.3024/second. Endpoint: POST /v1/models/bytedance/seedance/2.0/image-to-video/runs.
Seedance 2.0 animates a starting frame image into video, with optional end frame for controlled transitions. Supports synchronized audio generation.

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Overview

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Pricing

  • Base price: $0.3024/second
  • Note: Per second (720p)

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Seedance 2.0 Image to Video API

Endpoint: POST /v1/models/bytedance/seedance/2.0/image-to-video/runs

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Run the model

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Python

import requests

response = requests.post(
    "https://api.runflow.io/v1/models/bytedance/seedance/2.0/image-to-video/runs",
    headers={"Authorization": "Bearer RUNFLOW_API_KEY"},
    json={
        "input": {
            "prompt": "Clouds moving slowly across the sky, light shifting across the mountain peaks, gentle breeze in the grass",
            "image_url": "https://public.runflow.io/images/models/_base/landscape-mountain.png"
        },
        "callback_url": "https://your-server.com/webhook"
    },
)

data = response.json()
print(data)

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Node.js

const response = await fetch(
  "https://api.runflow.io/v1/models/bytedance/seedance/2.0/image-to-video/runs",
  {
    method: "POST",
    headers: {
      "Authorization": "Bearer RUNFLOW_API_KEY",
      "Content-Type": "application/json",
    },
    body: JSON.stringify({
        "input": {
            "prompt": "Clouds moving slowly across the sky, light shifting across the mountain peaks, gentle breeze in the grass",
            "image_url": "https://public.runflow.io/images/models/_base/landscape-mountain.png"
        },
        "callback_url": "https://your-server.com/webhook"
    }),
  }
);

const data = await response.json();
console.log(data);

​
cURL

curl -X POST https://api.runflow.io/v1/models/bytedance/seedance/2.0/image-to-video/runs \
  -H "Authorization: Bearer $RUNFLOW_API_KEY" \
  -H "Content-Type: application/json" \
  --data-binary @- <<'JSON'
{
    "input": {
        "prompt": "Clouds moving slowly across the sky, light shifting across the mountain peaks, gentle breeze in the grass",
        "image_url": "https://public.runflow.io/images/models/_base/landscape-mountain.png"
    },
    "callback_url": "https://your-server.com/webhook"
}
JSON

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Request parameters

ParameterTypeRequiredDescription
inputobjectrequiredModel input parameters. See “Input schema” below.
callback_urlstring | nulloptionalWebhook URL - POSTed when the run reaches a terminal state.
metadataobject | nulloptionalArbitrary key-value pairs attached to the run.

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Input schema

FieldTypeRequiredAllowed valuesDescription
image_urlimagerequiredAnyThe URL of the starting frame image to animate. Supported formats: JPEG, PNG, WebP. Max 30 MB.
promptstringrequiredAnyThe text prompt describing the desired motion and action for the video.
end_image_urlimageoptionalAnyThe URL of the image to use as the last frame of the video. When provided, the generated video will transition from the starting image to this ending image. Supported formats: JPEG, PNG, WebP. Max 30 MB.
aspect_ratiostringoptionalauto, 21:9, 16:9, 4:3, 1:1, 3:4, 9:16The aspect ratio of the generated video. Auto infers from the input image.
durationstringoptionalauto, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15Duration of the video in seconds. Supports 4 to 15 seconds, or auto.
resolutionstringoptional480p, 720p, 1080pVideo resolution - 480p for faster generation, 720p for balance.
generate_audiobooleanoptionalAnyWhether to generate synchronized audio for the video.
seedintegeroptionalAnyRandom seed for reproducibility.
end_user_idstringoptionalAnyThe unique user ID of the end user.

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Output schema

FieldTypeDescription
outputsjsonUnified output array - one entry per generated artifact with url/type/width/height/duration/etc.
seedjsonThe seed used for generation.
nsfw_detectedjsontrue if the provider flagged output as NSFW, false if cleared, null if not checked.
timingjsonProvider timing info (inference_ms etc.), or null.

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Callback payload

When you provide a callback_url, Runflow POSTs to it once the run reaches a terminal state.
FieldTypeDescription
eventstringEvent type: “run.completed”, “run.failed”, or “run.cancelled”.
run_idstringThe unique identifier of the run.
statusstringTerminal status: “succeeded”, “failed”, or “cancelled”.
outputobject | nullThe run output. Null if the run failed or was cancelled.
duration_msnumber | nullTotal run duration in milliseconds.
created_atstring | nullISO 8601 timestamp when the run was created.
completed_atstring | nullISO 8601 timestamp when the run reached terminal state.
metadataobject | nullThe metadata object passed at run creation, if any.
  • Retries: 3 attempts with exponential backoff (1s, 2s). Retries on 5xx / network errors only.
  • Headers: Runflow-Request-Id is always sent. Runflow-Signature is sent if a signing secret is configured.

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Additional Resources

Browse all models

Browse the catalog.

Run lifecycle

Callbacks, polling, statuses.

Callbacks

Handle async results.

Pricing

How requests bill out.