Seedance 2.0 API: Multimodal Video Generation

Overview

Seedance 2.0 is a ByteDance video generation model for prompt-only video, first-and-last-frame animation, and multimodal reference workflows. Use this page when you are ready to call the API after trying the model in the APIXO playground.

Capability	Value
Model ID	`seedance-2-0`
Modes	`text-to-video`, `first_and_last_frames`, `omni_reference`
Prompt	Required non-empty string
Resolutions	`480p`, `720p`, `1080p`, `4k`
Durations	Any integer from `4` through `15` seconds
Aspect ratios	`auto`, `16:9`, `4:3`, `1:1`, `3:4`, `9:16`, `21:9`
Reference images	1-2 URLs for `first_and_last_frames`; 1-9 URLs for `omni_reference`
Reference video/audio	1-3 URLs each for `omni_reference`; each file 2-15 seconds, total max 15 seconds per media type
Output	MP4 video URL array in `resultJson.resultUrls`

Endpoint and authentication

Base URL:

https://api.apixo.ai/api/v1

Method	Endpoint	Purpose
`POST`	`/generateTask/seedance-2-0`	Submit a generation task
`GET`	`/statusTask/seedance-2-0?taskId={taskId}`	Poll task status and retrieve results

All requests require your APIXO API key:

Authorization: Bearer YOUR_API_KEY

Submit requests also require:

Content-Type: application/json

Copy-paste async quickstart

This minimal request submits a text-to-video task and returns a taskId.

curl -X POST "https://api.apixo.ai/api/v1/generateTask/seedance-2-0" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "request_type": "async",
    "input": {
      "mode": "text-to-video",
      "prompt": "a cinematic tracking shot through a rainy neon street",
      "resolution": "4k",
      "duration": 5,
      "aspect_ratio": "16:9",
      "sound": true,
      "web_search": false
    }
  }'

Successful response:

{
  "code": 200,
  "message": "success",
  "data": {
    "taskId": "task_12345678"
  }
}

Save the taskId; you need it to poll for the final result.

Poll for result

curl -X GET "https://api.apixo.ai/api/v1/statusTask/seedance-2-0?taskId=task_12345678" \
  -H "Authorization: Bearer YOUR_API_KEY"

Processing response:

{
  "code": 200,
  "message": "success",
  "data": {
    "taskId": "task_12345678",
    "state": "processing",
    "createTime": 1767965610929
  }
}

Success response:

{
  "code": 200,
  "message": "success",
  "data": {
    "taskId": "task_12345678",
    "state": "success",
    "resultJson": "{\"resultUrls\":[\"https://file.apixo.ai/video.mp4\"]}",
    "createTime": 1767965610929,
    "completeTime": 1767965890929,
    "costTime": 280000
  }
}

Failed response:

{
  "code": 200,
  "message": "success",
  "data": {
    "taskId": "task_12345678",
    "state": "failed",
    "failCode": "UPSTREAM_ERROR",
    "failMsg": "The service could not complete the task",
    "createTime": 1767965610929,
    "completeTime": 1767965620132
  }
}

Parse resultJson after state becomes success:

const payload = JSON.parse(data.resultJson);
const videoUrls = payload.resultUrls;

Request body

Text-to-video

{
  "request_type": "async",
  "input": {
    "mode": "text-to-video",
    "prompt": "a slow tracking shot through a foggy pine forest at dawn",
    "resolution": "4k",
    "duration": 10,
    "aspect_ratio": "16:9",
    "sound": true,
    "web_search": false
  }
}

First-and-last-frames

{
  "request_type": "async",
  "input": {
    "mode": "first_and_last_frames",
    "prompt": "turn the still frames into a smooth cinematic camera move",
    "image_urls": [
      "https://example.com/frame-start.png",
      "https://example.com/frame-end.png"
    ],
    "resolution": "720p",
    "duration": 5,
    "aspect_ratio": "9:16",
    "sound": true,
    "web_search": false
  }
}

Omni-reference

{
  "request_type": "async",
  "input": {
    "mode": "omni_reference",
    "prompt": "create a stylish product ad using the visual references and voice rhythm",
    "image_urls": [
      "https://example.com/product-shot.png"
    ],
    "video_urls": [
      "https://example.com/ref-motion.mp4"
    ],
    "audio_urls": [
      "https://example.com/ref-audio.mp3"
    ],
    "resolution": "720p",
    "duration": 6,
    "aspect_ratio": "auto",
    "sound": true,
    "web_search": false
  }
}

Parameters

string

default:"async"

Result delivery mode. Omit this field or use async for polling with statusTask, or use callback for webhook delivery.

string

Required when request_type is callback. Must be a public HTTPS URL that can receive the final task payload. See Webhooks.

object

required

Seedance 2.0 input parameters.

Show properties

string

required

Generation mode. Supported values: text-to-video, first_and_last_frames, omni_reference.

string

required

Text prompt describing the desired video. The backend trims whitespace and rejects empty prompts. Maximum length: 10000 characters.

string

default:"720p"

Output resolution. Supported values: 480p, 720p, 1080p, 4k. Values are trimmed and normalized to lowercase, so 4K and 4k are treated the same.

integer|string

default:"5"

Output duration in seconds. Supports integers from 4 through 15, including numeric strings such as "10".

string

default:"auto"

Output aspect ratio. Supported values: auto, 16:9, 4:3, 1:1, 3:4, 9:16, 21:9.

boolean

default:"true"

Whether to generate audio with the video. Must be a boolean when provided.

boolean

default:"false"

Whether to allow real-time web search during generation. Must be a boolean when provided.

boolean

default:"false"

Enables content safety filtering for this request. Defaults to false; must be a boolean when provided.

string[]

Reference image URLs. Required for first_and_last_frames with 1-2 images. Optional for omni_reference with up to 9 images.

string[]

Reference video URLs for omni_reference. Supports 1-3 URLs when provided. Each video must be 2-15 seconds, and total reference video duration cannot exceed 15 seconds.

string[]

Reference audio URLs for omni_reference. Supports 1-3 URLs when provided. Each audio file must be 2-15 seconds, and total reference audio duration cannot exceed 15 seconds.

Mode	Required media	Optional media	Billing note
`text-to-video`	None	None	Uses the no-video-reference rate.
`first_and_last_frames`	`image_urls` with 1-2 images	None	Uses the no-video-reference rate.
`omni_reference`	None by validation, unless `audio_urls` is supplied	`image_urls`, `video_urls`, `audio_urls`	Uses video-reference billing when `video_urls` is provided.

In omni_reference, audio-only requests are rejected. If you provide audio_urls, include at least one image or video reference as well.

Use public, directly accessible URLs for all reference media. Video and audio durations are checked before the task is submitted.

image_urls examples use URL strings. The backend also accepts object items with a non-empty url field and normalizes them to URL strings.

Response format

Submit task response

POST /generateTask/seedance-2-0 returns a task ID when the task is accepted:

integer

API status code. 200 means the task was accepted.

string

Human-readable status message.

string

Unique task identifier used with the status endpoint.

Status response fields

string

Unique task identifier.

string

Current task state: pending, processing, success, or failed.

string

JSON string containing generated video URLs in resultUrls. Present when state is success.

string

Machine-readable failure code. Present when state is failed.

string

Human-readable failure message. Present when state is failed.

integer

Task creation timestamp in Unix milliseconds.

integer

Task completion timestamp in Unix milliseconds. Present after completion.

integer

Processing duration in milliseconds. Present after completion when timing data is available.

object

Final billing snapshot under data.billing, returned on successful terminal status and callback responses for new tasks. Older tasks may omit this object; see Billing for compatibility rules.

string

Settlement status. The final snapshot uses final.

string

Opaque identifier of the billing rule captured when this task was created. Do not infer the rule from polling time.

number

Actual total reference-video duration in seconds. Zero without video references; this is not raised to the minimum billable input.

number

For new tasks with video references, ceil(outputVideoSeconds * 2 / 3), rounded upward to a whole second. Zero without video references or under the original rule.

number

The larger of inputVideoSeconds and minimumInputVideoSeconds; zero without video references.

number

Output duration used for billing, in seconds.

number

Total billed seconds: outputVideoSeconds + billableInputVideoSeconds.

string

Duration unit. The value is second.

Webhook callback mode

Use callback mode when your backend should receive the final result automatically instead of polling.

curl -X POST "https://api.apixo.ai/api/v1/generateTask/seedance-2-0" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "request_type": "callback",
    "callback_url": "https://your-server.com/webhooks/apixo",
    "input": {
      "mode": "first_and_last_frames",
      "prompt": "turn the still frames into a smooth cinematic camera move",
      "image_urls": [
        "https://example.com/frame-start.png",
        "https://example.com/frame-end.png"
      ],
      "resolution": "720p",
      "duration": 5,
      "aspect_ratio": "9:16",
      "sound": true,
      "web_search": false
    }
  }'

The callback payload uses the same top-level shape as status polling with code, message, and data. Successful callbacks include the final state and resultJson. Successful terminal callbacks for new tasks also include data.billing. See Webhooks for delivery requirements and retry behavior.

Billing

Seedance 2.0 is billed per second. The selected resolution and whether omni_reference includes video_urls determine the per-second unit price.

Configuration	APIXO price
`480p`, without video reference	`$0.0933 / second`
`480p`, with video reference	`$0.0573 / second`
`720p`, without video reference	`$0.20 / second`
`720p`, with video reference	`$0.124 / second`
`1080p`, without video reference	`$0.4933 / second`
`1080p`, with video reference	`$0.3047 / second`
`4k`, without video reference	`$1.04 / second`
`4k`, with video reference	`$0.622 / second`

Formula without video reference:

total cost = output duration * unit price

Formula with video reference:

billable seconds = output seconds + max(actual total reference video seconds, ceil(output seconds * 2 / 3))
total cost = billable seconds * unit price

text-to-video and first_and_last_frames always use the without-video-reference rate. omni_reference uses the with-video-reference rate only when video_urls is provided. Image and audio references do not add extra billable seconds. ceil rounds upward to the next whole second. The minimum applies once to the total reference-video duration, not separately to each video. For example, 5 output seconds with 3 actual reference seconds bills 5 + max(3, 4) = 9 seconds; 6 output seconds with 2 actual reference seconds bills 10 seconds. This rule applies to tasks created after the billing update. Existing tasks retain the rule captured at creation: with video references, (output duration + actual total reference video duration) * unit price; without video references, output duration only. Per-second prices, custom prices, and user discounts are unchanged. Polling or receiving a callback after the update does not change an existing task’s rule. Successful terminal status and callback responses for new tasks include data.billing. Duration values use seconds with three decimal places; minimumInputVideoSeconds is a whole-second ceiling. inputVideoSeconds remains the actual input duration, while billableInputVideoSeconds is the charged input duration. The snapshot remains stable on repeated polling. Older tasks may omit billing or the new fields; clients must not require them for historical tasks. For example, the billing snapshot for 5 output seconds with 3 reference-video seconds includes:

{
  "billing": {
    "settlementState": "final",
    "inputVideoSeconds": 3.000,
    "minimumInputVideoSeconds": 4.000,
    "billableInputVideoSeconds": 4.000,
    "outputVideoSeconds": 5.000,
    "totalBillableSeconds": 9.000,
    "unit": "second"
  }
}

For current route and market comparison pricing, see Pricing.

Latency and polling

Video generation is long-running. The user manual lists typical Seedance 2.0 generation time at about 4-8 minutes. Actual latency may vary by prompt complexity, duration, resolution, reference media accessibility, route queue load, and storage transfer time.

Workload	Typical generation time	Recommended first poll	Poll interval
Text-to-video or first-and-last-frames	4-8 minutes	300s after task creation	10s-20s
Omni-reference with image/video/audio inputs	4-8 minutes or longer	300s-400s after task creation	10s-20s

For production workloads, use callback mode to avoid frequent polling while video tasks run.

Result URLs are temporary. Download and store important outputs promptly after task completion. Rate limits and concurrency can vary by account, API key, and route. If you receive 429, slow down requests and retry with backoff. For account-level details, see System APIs.

Errors and troubleshooting

HTTP errors

Code	Meaning	What to do
`400`	Invalid request body, missing `input`, unsupported `mode`, missing `prompt`, invalid `resolution`, invalid `duration`, invalid `aspect_ratio`, invalid boolean value, or invalid media array	Fix the request before retrying
`401`	Missing or invalid API key	Check the `Authorization` header
`402`	Insufficient balance or quota	Add balance or switch account/key
`403`	Key or route cannot access the model	Check permissions and route strategy
`404`	Task not found when polling	Check the `taskId`
`429`	Rate limit or concurrency limit reached	Retry with exponential backoff
`500`	Server error or unknown task failure	Retry with backoff
`502`	Service error	Retry with backoff
`504`	Service timeout	Retry or use callback mode for long-running jobs

Validation notes

Condition	Backend behavior
Missing `input`	Request fails before task creation.
Missing, non-string, or empty `prompt`	Request fails before task creation.
Missing `mode`	Request fails before task creation.
Unsupported `mode`	Request fails before task creation. Supported values are `text-to-video`, `first_and_last_frames`, and `omni_reference`.
Missing `resolution`	Defaults to `720p`.
Unsupported `resolution`	Request fails before task creation. Supported values are `480p`, `720p`, `1080p`, and `4k`.
Missing `duration`	Defaults to `5`.
`duration` outside `4` through `15`	Request fails before task creation.
Missing `aspect_ratio`	Defaults to `auto`.
Unsupported `aspect_ratio`	Request fails before task creation.
`sound` or `web_search` is not a boolean	Request fails before task creation.
`first_and_last_frames` without `image_urls`	Request fails before task creation.
`first_and_last_frames` with more than 2 images	Request fails before task creation.
`omni_reference` with more than 9 images, 3 videos, or 3 audio files	Request fails before task creation.
`omni_reference` with only `audio_urls`	Request fails before task creation.
Reference video or audio shorter than 2 seconds or longer than 15 seconds	Request fails before task creation.
Total reference video duration or total reference audio duration over 15 seconds	Request fails before task creation.

Task failure codes

failCode identifies the task failure. Common values include:

Fail code	Meaning	What to do
`SensitiveContent`	Prompt or input/output content was rejected by safety checks	Change the prompt or reference media
`PromptInvalid`	Prompt was invalid or rejected	Rewrite the prompt and retry
`ImageFormatIncorrect`	Reference image format could not be processed	Use a public, direct image URL in a common image format
`RateLimited`	A rate limit was reached	Retry with exponential backoff
`Timeout`	The task timed out	Retry later or use callback mode
`StreamError`	Video generation failed due to a server error	Retry with backoff
`Unknown error`	An unknown task failure occurred	Retry with backoff or contact support with the `taskId`

See Error Codes for the full error reference.

​Overview

​Endpoint and authentication

​Copy-paste async quickstart

​Poll for result

​Request body

​Text-to-video

​First-and-last-frames

​Omni-reference

​Parameters

​Response format

​Submit task response

​Status response fields

​Webhook callback mode

​Billing

​Latency and polling

​Errors and troubleshooting

​HTTP errors

​Validation notes

​Task failure codes

​Related links

Overview

Endpoint and authentication

Copy-paste async quickstart

Poll for result

Request body

Text-to-video

First-and-last-frames

Omni-reference

Parameters

Response format

Submit task response

Status response fields

Webhook callback mode

Billing

Latency and polling

Errors and troubleshooting

HTTP errors

Validation notes

Task failure codes

Related links