LTX Video 2.5 Fast

Choose Text to Video to generate from a prompt, or Image to Video to animate a first frame with an optional last frame. Native audio included.


Model id	`ltx-2.5-fast-fal`
Media	video
Submit to	`POST /v1/videos`
Price	varies by tier and settings; `GET /v1/models/ltx-2.5-fast-fal/estimate` quotes it
Typical time	about 30.0 s

Text to Video

Generate video from a text prompt without image attachments. Select it with "mode": "text_to_video"; mode is required and is not inferred from the inputs. Required: mode, prompt, duration_seconds
Optional: aspect_ratio, generate_audio Resolution tiers: 720p, 1080p, 1440p, 2160p (send as tier).

{
  "model": "ltx-2.5-fast-fal",
  "prompt": "A slow tracking shot through a sunlit forest. Leaves rustle in the breeze.",
  "mode": "text_to_video",
  "aspect_ratio": "16:9",
  "duration_seconds": 6,
  "generate_audio": true,
  "tier": "1080p"
}

Field	Allowed	Default
`aspect_ratio`	`16:9`, `9:16`	`"16:9"`
`duration_seconds`	`tier=1080p`: `6`, `8`, `10`, `12`, `14`, `16`, `18`, `20`; `tier=1440p`: `6`, `8`, `10`; `tier=2160p`: `6`, `8`, `10`; `tier=720p`: `6`, `8`, `10`, `12`, `14`, `16`, `18`, `20`	`6`
`generate_audio`	`True`, `False`	`true`

Tier	Credits per second before discounts
`720p`	4.95
`1080p`	7.15
`1440p`	10.45
`2160p`	16.5

Image to Video

Animate a required first frame; optionally add a last frame. Select it with "mode": "image_to_video"; mode is required and is not inferred from the inputs. Required: mode, prompt, first_frame, duration_seconds
Optional: last_frame, aspect_ratio, generate_audio Resolution tiers: 720p, 1080p, 1440p, 2160p (send as tier).

{
  "model": "ltx-2.5-fast-fal",
  "prompt": "A slow tracking shot through a sunlit forest. Leaves rustle in the breeze.",
  "mode": "image_to_video",
  "aspect_ratio": "auto",
  "duration_seconds": 6,
  "generate_audio": true,
  "first_frame": "asset_…",
  "tier": "1080p"
}

Field	Allowed	Default
`aspect_ratio`	`auto`, `16:9`, `9:16`	`"auto"`
`duration_seconds`	`tier=1080p`: `6`, `8`, `10`, `12`, `14`, `16`, `18`, `20`; `tier=1440p`: `6`, `8`, `10`; `tier=2160p`: `6`, `8`, `10`; `tier=720p`: `6`, `8`, `10`, `12`, `14`, `16`, `18`, `20`	`6`
`generate_audio`	`True`, `False`	`true`
`first_frame`	asset id (up to 1)
`last_frame`	asset id (up to 1)

Tier	Credits per second before discounts
`720p`	4.95
`1080p`	7.15
`1440p`	10.45
`2160p`	16.5

Reference inputs take asset ids from POST /v1/uploads or an earlier output’s asset_id. Prices and allowed values come from the live catalog; GET /v1/models/ltx-2.5-fast-fal is always current.

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LTX Video 2.5 Fast

Text to Video

Image to Video

​Text to Video

​Image to Video

Text to Video

Image to Video