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# LTX-2.3

> LTX-2.3 (ltx-2-3-fast, ltx-2-3-pro) supports text-to-video, image-to-video, audio-to-video, retake, and extend at up to 4K.

LTX-2.3 comes in two variants: `ltx-2-3-fast` for speed and low cost, and `ltx-2-3-pro` for higher fidelity. Both produce portrait and landscape video up to 4K at cinematic frame rates.

## Supported endpoints

Audio-to-video, retake, and extend require `ltx-2-3-pro`.

| Endpoint       | ltx-2-3-fast | ltx-2-3-pro |
| -------------- | ------------ | ----------- |
| text-to-video  | ✓            | ✓           |
| image-to-video | ✓            | ✓           |
| audio-to-video | —            | ✓           |
| retake         | —            | ✓           |
| extend         | —            | ✓           |

## Support matrix

Resolutions, FPS values, and duration options supported by each variant.

> **Note**
>
> **Duration** applies to text-to-video and image-to-video only. For audio-to-video, output length
> follows your input audio — see [maximum input audio length](/api-documentation/api-reference/async-video-generation/submit-audio-to-video)
> on the API reference.

| Model            | Resolution | FPS            | Duration (seconds)           |
| ---------------- | ---------- | -------------- | ---------------------------- |
| **ltx-2-3-fast** | 720p       | 24, 25         | 6, 8, 10, 12, 14, 16, 18, 20 |
|                  | 720p       | 48, 50         | 6, 8, 10                     |
|                  | 1080p      | 24, 25         | 6, 8, 10, 12, 14, 16, 18, 20 |
|                  | 1080p      | 48, 50         | 6, 8, 10                     |
|                  | 1440p      | 24, 25, 48, 50 | 6, 8, 10                     |
|                  | 4K         | 24, 25, 48, 50 | 6, 8, 10                     |
| **ltx-2-3-pro**  | 720p       | 24, 25, 48, 50 | 6, 8, 10                     |
|                  | 1080p      | 24, 25, 48, 50 | 6, 8, 10                     |
|                  | 1440p      | 24, 25, 48, 50 | 6, 8, 10                     |
|                  | 4K         | 24, 25, 48, 50 | 6, 8, 10                     |

### Resolutions

| Resolution | 16:9 (landscape) | 9:16 (portrait) |
| ---------- | ---------------- | --------------- |
| 720p       | `1280x720`       | `720x1280`      |
| 1080p      | `1920x1080`      | `1080x1920`     |
| 1440p      | `2560x1440`      | `1440x2560`     |
| 4K         | `3840x2160`      | `2160x3840`     |