> ## Documentation Index
> Fetch the complete documentation index at: https://docs.gravitex.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Seedance 2.5 Notes

> model: seedance-2-5 — API differences from Seedance 2.0

## Introduction

Seedance 2.5 (`model: "seedance-2-5"`) shares the same endpoints as Seedance 2.0 (Base URL, authentication, asset library, task polling, and response format are all identical) — just switch `model` to `seedance-2-5` when calling [Create video generation](/en/api-reference/endpoint/seedance-2.0/create-video-generation). This page only lists **what's different in 2.5**; everything not mentioned here (auth, asset library, polling, error codes, etc.) is identical to 2.0 — see:

* [Create video generation](/en/api-reference/endpoint/seedance-2.0/create-video-generation) (base parameters, `content` array structure, mutual-exclusion rules)
* [Get video generation](/en/api-reference/endpoint/seedance-2.0/get-video-generation)
* [Create asset group](/en/api-reference/endpoint/seedance-2.0/create-asset-group) / [Create asset](/en/api-reference/endpoint/seedance-2.0/create-asset)
* [Get moderation result](/en/api-reference/endpoint/seedance-2.0/get-moderation-result)

## Key differences

| Item                               | Seedance 2.0                     | Seedance 2.5                 |
| ---------------------------------- | -------------------------------- | ---------------------------- |
| `duration`                         | `-1` or `4`–`15` seconds         | `-1` or `4`–`30` seconds     |
| Reference images `reference_image` | up to 9                          | up to 30                     |
| Reference videos `reference_video` | up to 3, total ≤ 15s             | up to 10                     |
| Reference audio `reference_audio`  | up to 3                          | up to 10                     |
| Video editing / extension          | Not supported                    | Supported, see "Rules" below |
| `output_format`                    | `mp4` only                       | Adds optional `mov`          |
| `resolution` (currently available) | `480p` / `720p` / `1080p` / `4K` | `480p` / `720p` / `1080p`    |

<Note>
  The higher reference-asset limits and longer duration are upstream Seedance 2.5 model capabilities — see the [Dreamina Seedance 2.5 tutorial](https://docs.byteplus.com/en/docs/ModelArk/2607688). The higher `duration` and reference-asset limits are already available; `resolution` billing tiers follow the table above and the actual pricing page.
</Note>

## Rules

Seedance 2.5 has no explicit task-type parameter. Instead, it infers which of the tasks below a request belongs to from the `role` of media items in `content` and the intent expressed in the prompt; the allowed range for `ratio` and `duration` also differs by task type:

| Task Type                            | Trigger Condition                                                                                                          | `ratio`                        | `duration`       |
| ------------------------------------ | -------------------------------------------------------------------------------------------------------------------------- | ------------------------------ | ---------------- |
| Text-to-video                        | No reference assets at all — text prompt only                                                                              | A specific ratio or `adaptive` | `-1` or `4`–`30` |
| Reference-to-video                   | Provides `reference_image`, `reference_video`, or `reference_audio`, and the prompt carries no editing/extension intent    | A specific ratio or `adaptive` | `-1` or `4`–`30` |
| Video editing                        | Provides a reference asset, and the prompt expresses an editing intent (add, remove, replace, modify, repaint, or restore) | Must be `adaptive`             | Must be `-1`     |
| Video extension                      | Provides a reference asset, and the prompt expresses an intent to extend forward/backward, continue, or carry on           | Must be `adaptive`             | `-1` or `4`–`30` |
| First-frame / first-last-frame video | Provides an image as `first_frame`, optionally paired with `last_frame`                                                    | Must be `adaptive`             | `-1` or `4`–`30` |

## Request examples (standard text-to-video / image-to-video)

Identical to 2.0 usage — just swap `model`:

```bash theme={null}
curl -X POST "https://api.gravitex.ai/v1/video/generations" \
  -H "Authorization: Bearer sk-xxxxxxxxxx" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "seedance-2-5",
    "content": [
      {"type": "text", "text": "Golden hour drone shot over rolling mountains, clouds rolling by"}
    ],
    "duration": 20,
    "resolution": "720p",
    "ratio": "16:9",
    "generate_audio": true
  }'
```

For parameter details, the `content` array structure, and `asset://` mapping rules, see [Create video generation](/en/api-reference/endpoint/seedance-2.0/create-video-generation).

Next: [Get video generation](/en/api-reference/endpoint/seedance-2.0/get-video-generation)