> ## Documentation Index
> Fetch the complete documentation index at: https://apidoc.cometapi.com/llms.txt
> Use this file to discover all available pages before exploring further.
# Create a Seedance video
> Create a Seedance video task on CometAPI. The size field accepts exact WxH values and ratio preset labels. Use the documented Seedance resolution table for predictable results.
The `size` field accepts exact `WxH` values and ratio preset labels. Ratio preset labels map to the model-specific default `WxH` values in the table below. If you need a specific `720p` or `1080p` output, pass the exact `WxH` value instead of only a ratio preset. Exact `WxH` support remains model-dependent, so use a documented size entry for the target model when the rendered resolution must stay fixed.
## Size support by model
The table below follows the official Seedance resolution mapping and keeps the published size values in one place.
For `1080p`, the rightmost column lists the documented `Seedance 1.5 Pro` and `Seedance 2.0` values. `Seedance 2.0 Fast` is not listed in that official `1080p` table.
| Resolution | Aspect ratio | Pixel values for Seedance 1.0 series | Pixel values for Seedance 1.5 Pro / Seedance 2.0 / Seedance 2.0 Fast |
| ---------- | ------------ | ------------------------------------ | -------------------------------------------------------------------- |
| `480p` | `16:9` | `864×480` | `864×496` |
| | `4:3` | `736×544` | `752×560` |
| | `1:1` | `640×640` | `640×640` |
| | `3:4` | `544×736` | `560×752` |
| | `9:16` | `480×864` | `496×864` |
| | `21:9` | `960×416` | `992×432` |
| `720p` | `16:9` | `1248×704` | `1280×720` |
| | `4:3` | `1120×832` | `1112×834` |
| | `1:1` | `960×960` | `960×960` |
| | `3:4` | `832×1120` | `834×1112` |
| | `9:16` | `704×1248` | `720×1280` |
| | `21:9` | `1504×640` | `1470×630` |
| `1080p` | `16:9` | `1920×1088` | `1920×1080` |
| | `4:3` | `1664×1248` | `1664×1248` |
| | `1:1` | `1440×1440` | `1440×1440` |
| | `3:4` | `1248×1664` | `1248×1664` |
| | `9:16` | `1088×1920` | `1080×1920` |
| | `21:9` | `2176×928` | `2206×946` |
## How ratio presets differ from exact WxH
Use a ratio preset when the model-specific default output size is acceptable. For the `doubao-seedance-1-5-pro` family, ratio-only requests use the `720p` row from the table above:
| Ratio preset | Default rendered size |
| ------------ | --------------------- |
| `16:9` | `1280x720` |
| `4:3` | `1112x834` |
| `1:1` | `960x960` |
| `3:4` | `834x1112` |
| `9:16` | `720x1280` |
| `21:9` | `1470x630` |
Use exact `WxH` when the rendered resolution must stay fixed. For example, `doubao-seedance-1-5-pro` can render `1920x1080` and `1080x1920` as requested. Exact `WxH` remains model-dependent. `doubao-seedance-2-0` can accept `1920x1080` and still render `1280x720`.
## OpenAPI
````yaml /api/openapi/video/seedance/post-seedance-create.openapi.json POST /v1/videos
openapi: 3.1.0
info:
title: Seedance Video Generation API
version: 1.0.0
description: >-
Create an asynchronous ByteDance Seedance video task through CometAPI. Set
size to either an exact WxH value such as 1280x720 or a ratio preset label
such as 16:9, 4:3, 1:1, 3:4, 9:16, or 21:9. Ratio preset labels map to
model-specific default render sizes. If you need a fixed 720p or 1080p
output, pass the exact WxH value instead of only a ratio preset. Exact WxH
support remains model-dependent. For example, doubao-seedance-1-5-pro can
render 1920x1080 as requested, while doubao-seedance-2-0 can accept
1920x1080 and still render 1280x720. Save the returned id and poll GET
/v1/videos/{id} until the status reaches completed.
servers:
- url: https://api.cometapi.com
security:
- bearerAuth: []
paths:
/v1/videos:
post:
summary: Create a Seedance video task
description: >-
Submit a text-to-video or image-to-video job for any Seedance model
family. The request body is multipart/form-data so that the optional
input_reference image can be uploaded in the same call. Set size to
either a ratio preset label or an exact WxH value. Ratio preset labels
map to model-specific default render sizes. If you need a fixed 720p or
1080p output, pass the exact WxH value instead of only a ratio preset.
Exact WxH support remains model-dependent. For example,
doubao-seedance-1-5-pro can render 1920x1080 as requested, while
doubao-seedance-2-0 can accept 1920x1080 and still render 1280x720.
Ratio-label support differs by model: doubao-seedance-1-0-pro and
doubao-seedance-1-5-pro support 16:9, 4:3, 1:1, 3:4, 9:16, and 21:9;
doubao-seedance-2-0 supports 16:9, 4:3, 1:1, 3:4, and 21:9;
doubao-seedance-2-0-fast supports 4:3, 3:4, 9:16, and 21:9.
Image-to-video is supported only by the Seedance 2.0 models
(doubao-seedance-2-0, doubao-seedance-2-0-fast); the 1.0 Pro and 1.5 Pro
models accept text prompts only. The endpoint returns immediately with a
task id; use GET /v1/videos/{id} to read the final result.
operationId: seedance_create_video
requestBody:
required: true
content:
multipart/form-data:
schema:
type: object
required:
- prompt
- model
properties:
prompt:
type: string
description: Text prompt that describes the video. Required.
example: >-
A slow cinematic camera push across a coastal landscape at
sunrise.
model:
type: string
description: >-
Seedance model id. Only the two 2.0 models accept
input_reference.
enum:
- doubao-seedance-2-0
- doubao-seedance-2-0-fast
- doubao-seedance-1-5-pro
- doubao-seedance-1-0-pro
example: doubao-seedance-2-0
seconds:
type: integer
description: >-
Video duration in seconds. The accepted range depends on the
model: doubao-seedance-2-0 and doubao-seedance-2-0-fast
accept 4 to 15, doubao-seedance-1-5-pro accepts 4 to 12, and
doubao-seedance-1-0-pro accepts 2 to 10. The default is 5
for every model.
minimum: 2
maximum: 15
default: 5
example: 5
size:
type: string
description: >-
Output size. Use either a ratio preset label such as 16:9,
4:3, 1:1, 3:4, 9:16, or 21:9, or an exact WxH value such as
1280x720. Ratio preset labels map to model-specific default
render sizes. If you need a fixed 720p or 1080p output, pass
the exact WxH value instead of only a ratio preset. Exact
WxH support remains model-dependent, and an undocumented or
unsupported raw WxH value can normalize to another size or
fail.
pattern: ^(16:9|4:3|1:1|3:4|9:16|21:9|[1-9]\d{2,3}x[1-9]\d{2,3})$
examples:
- '16:9'
- 1280x720
- 1920x1080
- '4:3'
- 1112x834
- '1:1'
- 960x960
- '3:4'
- 834x1112
- '9:16'
- 720x1280
- 1080x1920
- '21:9'
- 1470x630
example: 1280x720
input_reference:
type: string
format: binary
description: >-
Optional reference image. When included, the job runs in
image-to-video mode and uses the image as the visual anchor.
Only doubao-seedance-2-0 and doubao-seedance-2-0-fast accept
this field; sending it with a 1.0 Pro or 1.5 Pro model
returns HTTP 400.
encoding:
input_reference:
contentType: image/jpeg, image/png, image/webp
responses:
'200':
description: Task created. Save the returned id and poll GET /v1/videos/{id}.
content:
application/json:
schema:
$ref: '#/components/schemas/CreateVideoResponse'
example:
id: task_abc123
task_id: task_abc123
object: video
model: doubao-seedance-2-0
status: queued
progress: 0
created_at: 1776681149
'400':
description: >-
The request is missing a required field or contains an out-of-range
value.
content:
application/json:
schema:
$ref: '#/components/schemas/ErrorResponse'
examples:
missing_prompt:
summary: prompt field missing
value:
code: invalid_request
message: prompt is required
missing_model:
summary: model field missing
value:
error:
code: ''
message: model name is required
type: comet_api_error
invalid_duration:
summary: seconds outside the per-model range
value:
code: InvalidParameter
message: >-
the parameter duration specified in the request is not
valid
i2v_not_supported:
summary: input_reference sent with a 1.0 Pro or 1.5 Pro model
value:
code: InvalidParameter
message: >-
The parameter task_type specified in the request is not
valid: the specified task_type r2v does not support model
seedance-1-5-pro
'401':
description: The API key is missing or invalid.
content:
application/json:
schema:
$ref: '#/components/schemas/ErrorResponse'
examples:
invalid_token:
summary: Bearer token rejected
value:
error:
code: ''
message: invalid token
type: comet_api_error
x-codeSamples:
- lang: Shell
label: Text-to-video (Seedance 2.0, ratio 16:9)
source: |-
curl https://api.cometapi.com/v1/videos \
-H "Authorization: Bearer " \
-F 'prompt="A slow cinematic camera push across a coastal landscape at sunrise"' \
-F 'model="doubao-seedance-2-0"' \
-F 'seconds="4"' \
-F 'size="16:9"'
- lang: Shell
label: Text-to-video (Seedance 1.5 Pro, exact 1920x1080)
source: |-
curl https://api.cometapi.com/v1/videos \
-H "Authorization: Bearer " \
-F 'prompt="A slow cinematic camera push across a coastal landscape at sunrise"' \
-F 'model="doubao-seedance-1-5-pro"' \
-F 'seconds="4"' \
-F 'size="1920x1080"'
- lang: Python
label: Text-to-video (Seedance 2.0, ratio 16:9)
source: |
import requests
response = requests.post(
"https://api.cometapi.com/v1/videos",
headers={"Authorization": "Bearer "},
data={
"prompt": "A slow cinematic camera push across a coastal landscape at sunrise",
"model": "doubao-seedance-2-0",
"seconds": "4",
"size": "16:9",
},
timeout=30,
)
response.raise_for_status()
print(response.json())
- lang: Python
label: Text-to-video (Seedance 2.0, request 1920x1080)
source: |
import requests
response = requests.post(
"https://api.cometapi.com/v1/videos",
headers={"Authorization": "Bearer "},
data={
"prompt": "A slow cinematic camera push across a coastal landscape at sunrise",
"model": "doubao-seedance-2-0",
"seconds": "4",
"size": "1920x1080",
},
timeout=30,
)
response.raise_for_status()
print(response.json())
- lang: JavaScript
label: Text-to-video (Seedance 2.0, ratio 16:9)
source: >
const form = new FormData();
form.append("prompt", "A slow cinematic camera push across a coastal
landscape at sunrise");
form.append("model", "doubao-seedance-2-0");
form.append("seconds", "4");
form.append("size", "16:9");
const response = await fetch("https://api.cometapi.com/v1/videos", {
method: "POST",
headers: { Authorization: "Bearer " },
body: form,
});
const result = await response.json();
console.log(result);
- lang: JavaScript
label: Text-to-video (Seedance 1.5 Pro, exact 1920x1080)
source: >
const form = new FormData();
form.append("prompt", "A slow cinematic camera push across a coastal
landscape at sunrise");
form.append("model", "doubao-seedance-1-5-pro");
form.append("seconds", "4");
form.append("size", "1920x1080");
const response = await fetch("https://api.cometapi.com/v1/videos", {
method: "POST",
headers: { Authorization: "Bearer " },
body: form,
});
const result = await response.json();
console.log(result);
components:
schemas:
CreateVideoResponse:
type: object
required:
- id
- object
- model
- status
- progress
- created_at
properties:
id:
type: string
description: Task id. Use it as the path parameter for GET /v1/videos/{id}.
task_id:
type: string
description: Alias of id returned for compatibility. The value matches id.
object:
type: string
description: Object type, always video.
model:
type: string
description: Echo of the requested model id.
status:
type: string
description: Initial task status. Newly created tasks are returned as queued.
enum:
- queued
- in_progress
- completed
- failed
- error
progress:
type: integer
minimum: 0
maximum: 100
description: Completion percentage. 0 at creation.
created_at:
type: integer
description: Task creation time as a Unix timestamp in seconds.
additionalProperties: true
ErrorResponse:
description: >-
Error body. The endpoint returns one of two shapes depending on where
the validation fails.
oneOf:
- type: object
properties:
code:
type:
- string
- 'null'
description: Short error code such as invalid_request or InvalidParameter.
message:
type: string
description: Human-readable error message.
required:
- message
additionalProperties: true
- type: object
properties:
error:
type: object
properties:
code:
type:
- string
- 'null'
message:
type: string
type:
type: string
description: Error category, for example comet_api_error.
required:
- message
- type
additionalProperties: true
required:
- error
additionalProperties: true
securitySchemes:
bearerAuth:
type: http
scheme: bearer
description: Bearer token authentication. Use your CometAPI key.
````