curl --request POST \
  --url https://api.evolink.ai/v1/videos/generations \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "model": "seedance-2.5-text-to-video",
  "prompt": "A macro lens focuses on a green glass frog on a leaf. The focus gradually shifts from its smooth skin to its completely transparent abdomen, where a bright red heart is beating powerfully and rhythmically.",
  "duration": 8,
  "quality": "720p",
  "aspect_ratio": "16:9",
  "generate_audio": true,
  "content_filter": true
}
'

{
  "created": 1761313744,
  "id": "task-unified-1774857405-abc123",
  "model": "seedance-2.5-text-to-video",
  "object": "video.generation.task",
  "progress": 0,
  "status": "pending",
  "task_info": {
    "can_cancel": true,
    "estimated_time": 165,
    "video_duration": 8
  },
  "type": "video",
  "usage": {
    "billing_rule": "per_second",
    "credits_reserved": 50,
    "user_group": "default"
  }
}

{
  "error": {
    "code": "invalid_parameter",
    "message": "Invalid request parameters",
    "type": "invalid_request_error"
  }
}

{
  "error": {
    "code": "unauthorized",
    "message": "Invalid or expired token",
    "type": "authentication_error"
  }
}

{
  "error": {
    "code": "insufficient_quota",
    "message": "Insufficient quota. Please top up your account.",
    "type": "insufficient_quota"
  }
}

{
  "error": {
    "code": "model_access_denied",
    "message": "Token does not have access to model: seedance-2.5-reference-to-video",
    "type": "invalid_request_error"
  }
}

{
  "error": {
    "code": "rate_limit_exceeded",
    "message": "Too many requests, please try again later",
    "type": "rate_limit_error"
  }
}

{
  "error": {
    "code": "internal_error",
    "message": "Internal server error",
    "type": "api_error"
  }
}

Seedance 2.5

Seedance 2.5 Complete Parameter Guide

Unified API for all Seedance 2.5 models, select a specific model via the model parameter

5 Generation Modes:

Text-to-Video: Generate video from pure text descriptions, supports web search enhancement
Image-to-Video: Use 1-2 images as first/last frames to drive video generation
Reference-to-Video: Mixed multimodal reference from images, videos, and audio
Video Edit: Edit an input video — replace subjects, add or remove objects, restyle regions
Video Extend: Extend an input video forward or backward
Now supports AIGC realistic human materials
Asynchronous processing mode, use the returned task ID to query status
Generated video links are valid for 24 hours, please save them promptly

POST

videos

generations

curl --request POST \
  --url https://api.evolink.ai/v1/videos/generations \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "model": "seedance-2.5-text-to-video",
  "prompt": "A macro lens focuses on a green glass frog on a leaf. The focus gradually shifts from its smooth skin to its completely transparent abdomen, where a bright red heart is beating powerfully and rhythmically.",
  "duration": 8,
  "quality": "720p",
  "aspect_ratio": "16:9",
  "generate_audio": true,
  "content_filter": true
}
'

{
  "created": 1761313744,
  "id": "task-unified-1774857405-abc123",
  "model": "seedance-2.5-text-to-video",
  "object": "video.generation.task",
  "progress": 0,
  "status": "pending",
  "task_info": {
    "can_cancel": true,
    "estimated_time": 165,
    "video_duration": 8
  },
  "type": "video",
  "usage": {
    "billing_rule": "per_second",
    "credits_reserved": 50,
    "user_group": "default"
  }
}

{
  "error": {
    "code": "invalid_parameter",
    "message": "Invalid request parameters",
    "type": "invalid_request_error"
  }
}

{
  "error": {
    "code": "unauthorized",
    "message": "Invalid or expired token",
    "type": "authentication_error"
  }
}

{
  "error": {
    "code": "insufficient_quota",
    "message": "Insufficient quota. Please top up your account.",
    "type": "insufficient_quota"
  }
}

{
  "error": {
    "code": "model_access_denied",
    "message": "Token does not have access to model: seedance-2.5-reference-to-video",
    "type": "invalid_request_error"
  }
}

{
  "error": {
    "code": "rate_limit_exceeded",
    "message": "Too many requests, please try again later",
    "type": "rate_limit_error"
  }
}

{
  "error": {
    "code": "internal_error",
    "message": "Internal server error",
    "type": "api_error"
  }
}

Authorizations

Authorization

string

header

required

##All endpoints require Bearer Token authentication##

Get API Key:

Visit the API Key Management Page to obtain your API Key

Add to request header:

Authorization: Bearer YOUR_API_KEY

Body

application/json

model

enum<string>

required

Video generation model name

Model ID	Mode	Input materials
`seedance-2.5-text-to-video`	Text-to-Video	`prompt`
`seedance-2.5-image-to-video`	Image-to-Video	`prompt` + `image_urls`
`seedance-2.5-reference-to-video`	Reference-to-Video	`prompt` + `image_urls` / `video_urls` / `audio_urls`
`seedance-2.5-video-edit`	Video Edit	`prompt` + `video_urls`
`seedance-2.5-video-extend`	Video Extend	`prompt` + `video_urls`

Available options:

seedance-2.5-text-to-video,

seedance-2.5-image-to-video,

seedance-2.5-reference-to-video,

seedance-2.5-video-edit,

seedance-2.5-video-extend

Example:

"seedance-2.5-text-to-video"

prompt

string

required

Text prompt describing the desired video. Supports both Chinese and English, recommended no more than 500 characters for Chinese or 1000 words for English. Maximum prompt length: 10000 tokens

Prompt usage for different models:

Text-to-Video: Pure text description, does not support using image_urls, video_urls, audio_urls in the prompt
Image-to-Video: Pure text description, does not support using video_urls, audio_urls in the prompt
Reference-to-Video: When referring to input materials, prefer explicit tags such as @image1, @video1, and @audio1. Tag numbers follow the order of the corresponding URL array and start at 1. Natural-language numbering may still be understood, but explicit tags provide a clearer mapping between each material and its intended use
Video Edit: Must state the editing intent and use @video1, @image1 to indicate what each material is for
Video Extend: Must state the extension direction (forward / backward) and use @video1 to indicate the video being extended

Keep editing / extension intent out of Reference-to-Video prompts (edit the video, add, remove / delete, change / replace, extend forward / backward, continue): such wording makes the request validated as Video Edit / Video Extend, so an aspect_ratio other than adaptive (or a duration other than -1 for edit tasks) makes the task fail later, with no error at submission. For those needs, switch model directly to seedance-2.5-video-edit / seedance-2.5-video-extend

Example:

"Use the first-person perspective framing of @video1 throughout, and use @audio1 as background music throughout. First-person perspective fruit tea promotional video..."

image_urls

string<uri>[]

Image URL array

Applicable models and quantity limits:

Text-to-Video: Not supported
Image-to-Video: Required, 1-2 images
Reference-to-Video: Optional, 1-30 images
Video Edit: Optional, 1-30 images
Video Extend: Optional, 1-30 images

Image-to-Video image behavior:

Image Count	Behavior	Role
1	First frame image-to-video	Automatically set as `first_frame`
2	First and last frame image-to-video	1st image -> `first_frame`, 2nd image -> `last_frame`

Reference-to-Video image roles:

Style reference, product image, character appearance, first/last frame (specified via prompt)

Requirement: At least one of image_urls, video_urls, or audio_urls must be provided.

Image requirements:

Supported formats: .jpeg, .png, .webp
Aspect ratio (width/height): 0.4 ~ 2.5
Width/height pixels: 300 ~ 6000 px
Max size per image: 30MB
Total request body size must not exceed 64MB
When providing first and last frames, both images can be identical. If aspect ratios differ, the first frame takes priority and the last frame will be automatically cropped to match
Image URLs must be directly accessible by the server

Required array length: 1 - 30 elements

Example:

[
  "https://example.com/ref1.jpg",
  "https://example.com/ref2.jpg"
]

video_urls

string<uri>[]

Reference video URL array, optional; 1–10 videos when provided

Applies to the Reference-to-Video, Video Edit and Video Extend models, other models do not support this parameter

Required for Video Edit / Video Extend: at least 1 video, the first one being the video to edit or extend.

Requirement: At least one of image_urls, video_urls, or audio_urls must be provided.

Role description:

Media Type	Role	Typical Usage
Video	`reference_video`	Camera movement reference, motion reference, original video for editing/extension

Video requirements:

Supported formats: .mp4, .mov
Resolution: 480p, 720p, 1080p, 4K
Duration per video: 2 ~ 30 seconds, max 10 videos, total duration of all videos ≤ 30 seconds
Aspect ratio (width/height): 0.4 ~ 2.5
Width/height pixels: 300 ~ 6000 px
Frame pixels (width × height): 409,600 ~ 8,295,044 (e.g., 640×640 ~ 3326×2494)
Max size per video: 200MB
Frame rate: 24 ~ 60 FPS
Total request body size must not exceed 64MB, do not use Base64 encoding
Specific codec, resolution, and other media validity checks are performed by the model
Using video references will increase costs (input video duration is counted in billing)
Video URLs must be directly accessible by the server

Required array length: 1 - 10 elements

Example:

["https://example.com/reference.mp4"]

audio_urls

string<uri>[]

Reference audio URL array, optional; 1–10 clips when provided

Applies to the Reference-to-Video, Video Edit and Video Extend models, other models do not support this parameter

Requirement: At least one of image_urls, video_urls, or audio_urls must be provided.

Role description:

Media Type	Role	Typical Usage
Audio	`reference_audio`	Background music, sound effects, voice/dialogue reference

Audio requirements:

Supported formats: .wav, .mp3
Duration per clip: 2 ~ 30 seconds, max 10 clips, total duration of all audio ≤ 30 seconds
Max size per clip: 15MB
Total request body size must not exceed 64MB, do not use Base64 encoding
Audio URLs must be directly accessible by the server

Required array length: 1 - 10 elements

Example:

["https://example.com/bgm.mp3"]

duration

integer

default:5

Output video duration (seconds), defaults to 5 seconds

Details:

Supports any integer value between 4–30 seconds
-1: automatic duration, the model picks a length within 4–30 seconds and billing follows the actual output length
Duration directly affects billing
Video Edit only supports -1: the output length follows the input video and cannot be customized

Applicable to all 5 models

Example:

10

quality

enum<string>

default:720p

Video resolution, defaults to 720p

Options:

480p: Lower clarity, lower cost
720p: Standard clarity, this is the default
1080p: Ultra HD clarity

Applicable to all 5 models

Available options:

480p,

720p,

1080p

Example:

"720p"

aspect_ratio

enum<string>

default:adaptive

Video aspect ratio, defaults to adaptive

Options:

16:9 (landscape), 9:16 (portrait), 1:1 (square), 4:3, 3:4, 21:9 (ultrawide)
adaptive: Automatically select the best ratio

adaptive behavior per model:

Text-to-Video: Automatically selected based on prompt content
Image-to-Video: Automatically adapts based on first frame image aspect ratio (this model only supports adaptive, fixed ratios cannot be specified)
Reference-to-Video: Priority: video material ratio > image material ratio > prompt inference
Video Edit / Video Extend: Follows the ratio of the first input video (both models only support adaptive)

Pixel values per resolution:

Aspect Ratio	480p	720p
16:9	854×480	1280×720
4:3	752×560	1112×834
1:1	640×640	960×960
3:4	560×752	834×1112
9:16	480×854	720×1280
21:9	992×432	1470×630

Applicable to all 5 models (Image-to-Video / Video Edit / Video Extend accepts adaptive only)

Available options:

16:9,

9:16,

1:1,

4:3,

3:4,

21:9,

adaptive

Example:

"16:9"

generate_audio

boolean

default:true

Whether to generate synchronized audio, defaults to true

true: Video includes synchronized audio (voice, sound effects, background music) at no additional charge
false: Output silent video

Applicable to all 5 models

Example:

true

content_filter

boolean

default:true

Content filter, enabled by default true

Options:

true: Standard content safety check, this is the default
false: Relaxes content restrictions, billed at +10% (1.1x). Illegal and prohibited content is always enforced regardless of this setting

Mutually exclusive with web search:

content_filter: false and model_params.web_search: true cannot be used together; sending both returns a 400 parameter error
Keep content_filter: true (the default) when web search is needed

Example:

true

output_format

enum<string>

default:mp4

Output container format, defaults to mp4

Options:

mp4: H.264 encoding with the best compatibility and standard color precision, this is the default
mov: H.264 + yuv444p chroma sampling + PCM audio for higher color fidelity, recommended for color grading, keying and compositing workflows. Browser inline playback may not support it; download and play with VLC / mpv / ffplay. No extra charge

Available options:

mp4,

mov

Example:

"mp4"

model_params

object

Model extension parameters

Only applicable to Text-to-Video models

Show child attributes

callback_url

string<uri>

HTTPS callback URL for task completion

Callback timing:

Triggered when the task is completed, failed, or cancelled
Sent after billing confirmation is complete

Security restrictions:

Only HTTPS protocol is supported
Callbacks to private IP addresses are prohibited (127.0.0.1, 10.x.x.x, 172.16-31.x.x, 192.168.x.x, etc.)
URL length must not exceed 2048 characters

Callback mechanism:

Timeout: 10 seconds
Up to 3 retries after failure (at 1/2/4 seconds after failure respectively)
Callback response body format is consistent with the task query endpoint response format
A 2xx status code is considered successful; other status codes trigger retries

Example:

"https://your-domain.com/webhooks/video-task-completed"

Response

Video generation task created successfully

created

integer

Task creation timestamp

Example:

1761313744

string

Task ID

Example:

"task-unified-1774857405-abc123"

model

string

Actual model name used

Example:

"seedance-2.5-text-to-video"

object

enum<string>

Specific type of the task

Available options:

video.generation.task

progress

integer

Task progress percentage (0-100)

Required range: 0 <= x <= 100

Example:

0

status

enum<string>

Task status

Available options:

pending,

processing,

completed,

failed

Example:

"pending"

task_info

object

Video task details

Show child attributes

type

enum<string>

Output type of the task

Available options:

text,

image,

audio,

video

Example:

"video"

usage

object

Usage and billing information

Show child attributes

Image Series

Video Series

Audio Series

Text Series

Account Management

Task Management

File Management

Seedance 2.5 Complete Parameter Guide

Authorizations

Body

Response