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

# LTX Video 2.3 Extend

> Extend an existing clip with newly generated, continuous footage and native audio using LTX-2.3.

Extend an existing clip with newly generated, continuous footage and native audio using LTX-2.3. Upload a video, describe what happens next.

| | |
| - | - |
| Model id | `ltx-2.3-extend-fal` |
| Media | video |
| Submit to | `POST /v1/videos` |
| Price | 7.8 credits per\_second before discounts |
| Typical time | about 60.0 s |

## Request

**Required:** `prompt`, `source_video`\
**Optional:** `duration_seconds`

```json theme={null}
{
  "model": "ltx-2.3-extend-fal",
  "prompt": "The dancer turns and walks out of frame toward the exit, camera holding steady.",
  "duration_seconds": 5,
  "source_video": "asset_…"
}
```

| Field | Allowed | Default |
| - | - | - |
| `duration_seconds` | `5`, `6`, `8`, `10`, `15`, `20` | `5` |
| `source_video` | asset id (up to 1) | |

Reference inputs take asset ids from [`POST /v1/uploads`](/uploads) or an earlier output's `asset_id`.
Prices and allowed values come from the live catalog; `GET /v1/models/ltx-2.3-extend-fal` is always current.


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