> ## 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.

# FLUX.3 Video

> Black Forest Labs FLUX.3 video generation with text, image, first/last-frame, exact keyframe, and video-extension modes with native audio.

Black Forest Labs FLUX.3 video generation with text, image, first/last-frame, exact keyframe, and video-extension modes with native audio.

| | |
| - | - |
| Model id | `flux-3-fal` |
| Media | video |
| Submit to | `POST /v1/videos` |
| Price | varies by tier and settings; `GET /v1/models/flux-3-fal/estimate` quotes it |
| Typical time | about 360.0 s |

## Text → Video

Generate a complete shot from text with native audio.

Select it with `"mode": "text_to_video"`, or leave `mode` out and the inputs decide.

**Required:** `prompt`, `duration_seconds`\
**Optional:** `aspect_ratio`, `generate_audio`

Resolution tiers: `720p`, `1080p` (send as `tier`).

```json theme={null}
{
  "model": "flux-3-fal",
  "prompt": "A slow aerial shot over a misty pine forest at dawn",
  "mode": "text_to_video",
  "aspect_ratio": "auto",
  "duration_seconds": 5,
  "tier": "720p"
}
```

| Field | Allowed | Default |
| - | - | - |
| `aspect_ratio` | `auto`, `21:9`, `2:1`, `16:9`, `4:3`, `1:1`, `3:4`, `9:16` | `"auto"` |
| `duration_seconds` | 5.0 – 20.0 seconds | `5` |
| `generate_audio` | `true`, `false` | `true` |

## Image → Video

Animate a single opening image into coherent motion.

Select it with `"mode": "image_to_video"`, or leave `mode` out and the inputs decide.

**Required:** `prompt`, `first_frame`, `duration_seconds`\
**Optional:** `aspect_ratio`, `generate_audio`

Resolution tiers: `720p`, `1080p` (send as `tier`).

```json theme={null}
{
  "model": "flux-3-fal",
  "prompt": "A slow aerial shot over a misty pine forest at dawn",
  "mode": "image_to_video",
  "aspect_ratio": "auto",
  "duration_seconds": 5,
  "first_frame": "asset_…",
  "tier": "720p"
}
```

| Field | Allowed | Default |
| - | - | - |
| `aspect_ratio` | `auto`, `21:9`, `2:1`, `16:9`, `4:3`, `1:1`, `3:4`, `9:16` | `"auto"` |
| `duration_seconds` | 5.0 – 20.0 seconds | `5` |
| `generate_audio` | `true`, `false` | `true` |
| `first_frame` | asset id (up to 1) | |

## First/Last Frame → Video

Generate a transition pinned to both an opening and closing image.

Select it with `"mode": "first_last_frame_to_video"`, or leave `mode` out and the inputs decide.

**Required:** `prompt`, `first_frame`, `last_frame`, `duration_seconds`\
**Optional:** `aspect_ratio`, `generate_audio`

Resolution tiers: `720p`, `1080p` (send as `tier`).

```json theme={null}
{
  "model": "flux-3-fal",
  "prompt": "A slow aerial shot over a misty pine forest at dawn",
  "mode": "first_last_frame_to_video",
  "aspect_ratio": "auto",
  "duration_seconds": 5,
  "first_frame": "asset_…",
  "last_frame": "asset_…",
  "tier": "720p"
}
```

| Field | Allowed | Default |
| - | - | - |
| `aspect_ratio` | `auto`, `21:9`, `2:1`, `16:9`, `4:3`, `1:1`, `3:4`, `9:16` | `"auto"` |
| `duration_seconds` | 5.0 – 20.0 seconds | `5` |
| `generate_audio` | `true`, `false` | `true` |
| `first_frame` | asset id (up to 1) | |
| `last_frame` | asset id (up to 1) | |

## Keyframes → Video

Pin up to 10 images to exact positions on a 24 fps timeline.

Select it with `"mode": "keyframes_to_video"`, or leave `mode` out and the inputs decide.

**Required:** `prompt`, `keyframes`, `duration_seconds`\
**Optional:** `aspect_ratio`, `generate_audio`

Resolution tiers: `720p`, `1080p` (send as `tier`).

```json theme={null}
{
  "model": "flux-3-fal",
  "prompt": "A slow aerial shot over a misty pine forest at dawn",
  "mode": "keyframes_to_video",
  "aspect_ratio": "auto",
  "duration_seconds": 5,
  "keyframes": [
    {
      "image": "asset_…",
      "frame_index": 0
    },
    {
      "image": "asset_…",
      "frame_index": 48
    }
  ],
  "tier": "720p"
}
```

| Field | Allowed | Default |
| - | - | - |
| `aspect_ratio` | `auto`, `21:9`, `2:1`, `16:9`, `4:3`, `1:1`, `3:4`, `9:16` | `"auto"` |
| `duration_seconds` | 5.0 – 20.0 seconds | `5` |
| `generate_audio` | `true`, `false` | `true` |
| `keyframes` | asset ids (up to 10) | |

## Extend Video

Continue an existing video from its final frames.

Select it with `"mode": "extend_video"`, or leave `mode` out and the inputs decide.

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

Resolution tiers: `720p`, `1080p` (send as `tier`).

```json theme={null}
{
  "model": "flux-3-fal",
  "prompt": "A slow aerial shot over a misty pine forest at dawn",
  "mode": "extend_video",
  "aspect_ratio": "auto",
  "duration_seconds": 5,
  "source_video": "asset_…",
  "tier": "720p"
}
```

| Field | Allowed | Default |
| - | - | - |
| `aspect_ratio` | `auto`, `21:9`, `2:1`, `16:9`, `4:3`, `1:1`, `3:4`, `9:16` | `"auto"` |
| `duration_seconds` | 5.0 – 20.0 seconds | `5` |
| `generate_audio` | `true`, `false` | `true` |
| `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/flux-3-fal` is always current.


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