> ## Documentation Index
> Fetch the complete documentation index at: https://apixo.ai/docs/llms.txt
> Use this file to discover all available pages before exploring further.
# Seedance 1.5 Pro
> ByteDance video generation API for text-to-video, image-to-video, and video extension workflows
## Overview
Seedance 1.5 Pro is a ByteDance video generation model for short text-to-video, image-to-video, and video extension 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-1-5-pro` |
| Modes | `text-to-video`, `image-to-video`, `video-extend` |
| Prompt length | 3-2500 characters |
| Reference images | 1-2 URLs for `image-to-video`; the second image is used as the end frame |
| Source video | Exactly 1 public video URL for `video-extend` |
| Aspect ratios | `auto`, `1:1`, `3:4`, `4:3`, `9:16`, `16:9`, `21:9` for `text-to-video` and `image-to-video` |
| Resolutions | `480p`, `720p`, `1080p` |
| Duration | 4-12 seconds; use `4`, `8`, or `12` for predictable tier matching |
| Audio | Required `sound` toggle |
| Output | Generated or extended video URL in `resultJson.resultUrls` |
## Endpoint and authentication
Base URL:
```text theme={null}
https://api.apixo.ai/api/v1
```
| Method | Endpoint | Purpose |
| ------ | ---------------------------------------------- | ------------------------------------- |
| `POST` | `/generateTask/seedance-1-5-pro` | Submit a generation task |
| `GET` | `/statusTask/seedance-1-5-pro?taskId={taskId}` | Poll task status and retrieve results |
All requests require your APIXO API key:
```http theme={null}
Authorization: Bearer YOUR_API_KEY
```
Submit requests also require:
```http theme={null}
Content-Type: application/json
```
## Copy-paste async quickstart
This minimal request submits a text-to-video task and returns a `taskId`.
```bash theme={null}
curl -X POST "https://api.apixo.ai/api/v1/generateTask/seedance-1-5-pro" \
-H "Authorization: Bearer YOUR_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"request_type": "async",
"input": {
"mode": "text-to-video",
"prompt": "a calm seaside sunrise with gentle camera dolly movement",
"resolution": "720p",
"duration": 8,
"sound": false,
"aspect_ratio": "auto",
"camera_fixed": false,
"seed": 123456,
"watermark": false
}
}'
```
Successful response:
```json theme={null}
{
"code": 200,
"message": "success",
"data": {
"taskId": "task_12345678"
}
}
```
Save the `taskId`; you need it to poll for the final result.
## Poll for result
```bash theme={null}
curl -X GET "https://api.apixo.ai/api/v1/statusTask/seedance-1-5-pro?taskId=task_12345678" \
-H "Authorization: Bearer YOUR_API_KEY"
```
Processing response:
```json theme={null}
{
"code": 200,
"message": "success",
"data": {
"taskId": "task_12345678",
"state": "processing",
"createTime": 1767965610929
}
}
```
Success response:
```json theme={null}
{
"code": 200,
"message": "success",
"data": {
"taskId": "task_12345678",
"state": "success",
"resultJson": "{\"resultUrls\":[\"https://file.apixo.ai/xxx.mp4\"]}",
"createTime": 1767965610929,
"completeTime": 1767965695412,
"costTime": 84483
}
}
```
Failed response:
```json theme={null}
{
"code": 200,
"message": "success",
"data": {
"taskId": "task_12345678",
"state": "failed",
"failCode": "SensitiveContent",
"failMsg": "Content violates upstream policy, please adjust the prompt",
"createTime": 1767965610929,
"completeTime": 1767965620132,
"costTime": 9203
}
}
```
Parse `resultJson` after `state` becomes `success`:
```javascript theme={null}
const payload = JSON.parse(data.resultJson);
const videoUrls = payload.resultUrls;
```
## Request body
### Text-to-video
```json theme={null}
{
"request_type": "async",
"input": {
"mode": "text-to-video",
"prompt": "a clean product showcase on a neutral background, subtle lighting shifts, steady camera",
"resolution": "720p",
"duration": 8,
"sound": false,
"aspect_ratio": "auto",
"camera_fixed": true,
"seed": 123456,
"watermark": false
}
}
```
### Image-to-video
```json theme={null}
{
"request_type": "async",
"input": {
"mode": "image-to-video",
"prompt": "animate this landscape with moving clouds and soft wind",
"image_urls": [
"https://example.com/start-frame.jpg",
"https://example.com/end-frame.jpg"
],
"resolution": "480p",
"duration": 4,
"sound": true,
"aspect_ratio": "1:1",
"camera_fixed": false,
"seed": 123456,
"watermark": false
}
}
```
### Video extend
```json theme={null}
{
"request_type": "async",
"input": {
"mode": "video-extend",
"prompt": "continue the same shot with a gentle smile and then a smooth ride-away",
"video_urls": [
"https://example.com/source.mp4"
],
"resolution": "720p",
"duration": 8,
"sound": true,
"camera_fixed": true,
"seed": 123456,
"watermark": false
}
}
```
## Parameters
Result delivery mode. Use `async` for polling with `statusTask`, or `callback` for webhook delivery.
Required when `request_type` is `callback`. Must be a public HTTPS URL that can receive the final task payload. See [Webhooks](/api-reference/webhooks).
Seedance 1.5 Pro input parameters.
Generation mode. Supported values: `text-to-video`, `image-to-video`, `video-extend`. If omitted, APIXO infers `image-to-video` when `image_urls` is present and `text-to-video` otherwise. Set `video-extend` explicitly when extending a source video.
Text prompt describing the desired video or continuation. Supports 3-2500 characters after trimming.
Reference image URLs. Required for `image-to-video`. Supports 1-2 URLs; when two are provided, the first is the start frame and the second is the end frame.
Source video URLs. Required for `video-extend`; provide exactly 1 public video URL. Do not use `video_urls` for `text-to-video` or `image-to-video`.
Output video resolution. Supported values: `480p`, `720p`, `1080p`.
Video duration in seconds. Accepts integer values from `4` to `12`; numeric strings are also accepted by the backend. Use `4`, `8`, or `12` for predictable tier matching.
Whether to generate audio with the video. Use `true` for generated sound, or `false` for a silent video.
Output aspect ratio for `text-to-video` and `image-to-video`. Supported values: `auto`, `1:1`, `3:4`, `4:3`, `9:16`, `16:9`, `21:9`.
Set `true` to request a stable camera view. For `video-extend`, the backend defaults this field to `true` when omitted.
Optional random seed for more reproducible results across retries and repeated runs.
Whether to keep the upstream watermark in the generated video when the selected route supports it.
Legacy `fixed_lens` is still accepted for compatibility, but new integrations should use `camera_fixed`.
## Response format
### Submit task response
`POST /generateTask/seedance-1-5-pro` returns a task ID when the task is accepted:
API status code. `200` means the task was accepted.
Human-readable status message.
Unique task identifier used with the status endpoint.
### Status response fields
Unique task identifier.
Current task state: `pending`, `processing`, `success`, or `failed`.
JSON string containing the generated or extended video URLs. Present when `state` is `success`.
Machine-readable failure code. Present when `state` is `failed`.
Human-readable failure message. Present when `state` is `failed`.
Task creation timestamp in Unix milliseconds.
Task completion timestamp in Unix milliseconds. Present after completion.
Processing duration in milliseconds. Present after completion when available.
## Webhook callback mode
Use callback mode when your backend should receive the final result automatically instead of polling.
```bash theme={null}
curl -X POST "https://api.apixo.ai/api/v1/generateTask/seedance-1-5-pro" \
-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": "video-extend",
"prompt": "continue the same scene with a smooth smile, then leave the frame naturally",
"video_urls": [
"https://example.com/source.mp4"
],
"resolution": "720p",
"duration": 8,
"sound": true,
"camera_fixed": true,
"seed": 123456,
"watermark": false
}
}'
```
The callback payload uses the same unified response shape as the status endpoint when the task reaches a final state. See [Webhooks](/api-reference/webhooks) for delivery requirements and retry behavior.
## Billing
Seedance 1.5 Pro is billed per second. The selected `resolution`, `duration`, and `sound` value determine the total cost for all supported modes, including `video-extend`.
| Resolution | `sound` | Price |
| ---------- | ------- | ----------------- |
| `480p` | `false` | `$0.012 / second` |
| `480p` | `true` | `$0.024 / second` |
| `720p` | `false` | `$0.024 / second` |
| `720p` | `true` | `$0.048 / second` |
| `1080p` | `false` | `$0.052 / second` |
| `1080p` | `true` | `$0.104 / second` |
Total cost is the per-second price multiplied by the billable duration. For example, `720p` with `sound: false` for 8 seconds costs `$0.192`.
For current route and market comparison pricing, see [Pricing](https://apixo.ai/pricing).
## Latency and polling
Actual latency may vary by prompt complexity, input media, mode, route selection, and current queue load. `video-extend` includes source clip analysis and final stitching, so it can take longer than direct text-to-video or image-to-video generation.
| Mode | Duration | Typical generation time | Recommended first poll | Poll interval |
| --------------------------------- | ------------ | ----------------------- | ----------------------- | ------------- |
| `text-to-video`, `image-to-video` | `4` seconds | 40s-60s | 40s after task creation | 5s-10s |
| `text-to-video`, `image-to-video` | `8` seconds | 60s-90s | 60s after task creation | 5s-10s |
| `text-to-video`, `image-to-video` | `12` seconds | 90s-120s | 90s after task creation | 5s-10s |
| `video-extend` | `4` seconds | 45s-75s | 45s after task creation | 5s-10s |
| `video-extend` | `8` seconds | 60s-110s | 60s after task creation | 5s-10s |
| `video-extend` | `12` seconds | 90s-150s | 90s after task creation | 5s-10s |
Video generation can take time. For production workloads, use callback mode to avoid frequent polling.
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](/api-reference/system).
## Errors and troubleshooting
### HTTP errors
| Code | Meaning | What to do |
| ----- | -------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------- |
| `400` | Invalid request body, missing required field, unsupported mode, unsupported resolution, invalid duration, malformed source URL array, or rejected prompt/media | 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 |
| `429` | Rate limit or concurrency limit reached | Retry with exponential backoff |
| `500` | Server error or unmapped upstream error | Retry with backoff; contact support if it repeats |
| `502` | Upstream error | Retry with backoff |
| `504` | Upstream timeout | Retry or use callback mode for long-running jobs |
### Task failure codes
| Fail code | Meaning | What to do |
| ------------------------- | ------------------------------------------------------------------------------------------------ | ---------------------------------------------------------------------------------------------------- |
| `MISSING_REQUIRED_PARAM` | A required field such as `prompt`, `video_urls`, `resolution`, `duration`, or `sound` is missing | Fix the request before retrying |
| `INVALID_PARAMETER` | One or more fields use an unsupported value or type | Check `mode`, media URLs, `resolution`, `duration`, `sound`, `camera_fixed`, `seed`, and `watermark` |
| `API_SERVICE_UNAVAILABLE` | Video extension processing or generation is temporarily unavailable | Retry later |
| `PromptInvalid` | The prompt was rejected or malformed | Rewrite the prompt and retry |
| `SensitiveContent` | The prompt or generated content violated upstream policy | Change the prompt or reference media |
| `ImageFormatIncorrect` | A reference image could not be accepted | Use a public JPG, PNG, or WebP image URL |
| `RateLimited` | The upstream route rate limited the task | Retry later with backoff |
| `Timeout` | The workflow did not finish in time | Retry, simplify the prompt, or use callback mode |
| `InsufficientBalance` | The route could not continue because of balance or quota | Add balance before retrying |
| `Unknown error` | The failure did not match a known public mapping | Retry or contact support with the `taskId` |
### Common validation fixes
| Symptom | Fix |
| ------------------------------------------ | ------------------------------------------------------------------------- |
| `mode` is rejected | Use `text-to-video`, `image-to-video`, or `video-extend` |
| `image_urls` is missing for image-to-video | Provide 1-2 public image URLs |
| `video_urls` is missing for video-extend | Set `input.mode` to `video-extend` and provide exactly 1 public video URL |
| `resolution` is rejected | Use `480p`, `720p`, or `1080p` |
| `duration` is rejected | Send an integer from `4` to `12` |
| `sound` is rejected | Send a boolean: `true` or `false` |
| Prompt length error | Keep the trimmed prompt within 3-2500 characters |
See [Error Codes](/api-reference/errors) for the full error reference.
## Related links
* [Generation API Overview](/models)
* [Generate Task](/api-reference/generate-task)
* [Status Task](/api-reference/status-task)
* [Webhooks](/api-reference/webhooks)
* [Error Codes](/api-reference/errors)
* [Parameter Specification](/api-reference/parameters)
* [Routing Strategies](/concepts/routing-strategies)
* [Pricing](https://apixo.ai/pricing)