Grok Imagine 1.5 Video

What is Grok Imagine 1.5 Video?#

Grok Imagine 1.5 Video is the official API build of xAI's Grok Imagine 1.5 model, generally available since June 2026. It is image-to-video only: you supply a start_image_url to animate, and the prompt is optional guidance for how it should move. Videos run from 1 to 15 seconds at 480p, 720p, or 1080p, with sound effects, ambience, and dialogue generated in the same pass.

It is the quality route of the family. On the Arena image-to-video board it is the highest-ranked xAI model and sits ahead of every Veo 3.1 variant. If you need text-to-video, reference images, or style presets, use Grok Imagine Video, the speed-optimized build of the same model, on this page.

Key features of Grok Imagine 1.5 Video#

Best for#

Use cases#

Start with a clean still and let the prompt say what moves and what it sounds like. A cosmetics brand can pass a packaging shot and get a slow orbit with the product locked in frame and a soft ambient bed; a studio can animate a glass render so surfaces ripple and refract. Because the composition arrives fixed in the start image, this route is predictable in a way text-to-video is not: the model is deciding motion and sound, not subject.

A practical split is to draft on Grok Imagine Video and finish here. That build generates from a prompt alone and returns sooner, which suits exploring ideas. Once a frame is right, animate it here at 1080p for the version you ship.

Limitations#

There is no text-to-video on this route; a start image is required. It takes no reference images, no style presets, and no aspect ratio parameter, so the output follows the start image. Negative prompts are ignored, so describe what you want rather than what to avoid. Grok Imagine Video Extend and Grok Imagine Upscale do not accept task IDs from this route; they only work on videos from the speed-optimized build.

Grok Imagine 1.5 Video vs Grok Imagine Video#

Both run Grok Imagine 1.5. This is the official API build; the other is a speed-optimized build of the same model, faster in exchange for a small amount of quality. Both generate sound in the same pass.

Pick this route when you have the opening frame and want 1080p. Pick Grok Imagine Video when you need to generate from a prompt, use references, or extend and upscale the result.

API examples#

Call Grok Imagine 1.5 Video from any language by POSTing to /v1/tasks. Full parameter docs live at docs.unifically.com/models/video/xai/grok-imagine-1.5-video.

curl -X POST https://api.unifically.com/v1/tasks \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -d '{
    "model": "xai/grok-imagine-1.5-video",
    "input": {
      "start_image_url": "https://files.unifically.com/your-start-frame.jpg",
      "prompt": "Camera slowly zooms in while clouds drift across the sky. AUDIO: soft wind, distant birds",
      "duration": 10,
      "resolution": "1080p"
    }
  }'

The prompt is optional. A start image alone is a valid request:

curl -X POST https://api.unifically.com/v1/tasks \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -d '{
    "model": "xai/grok-imagine-1.5-video",
    "input": {
      "start_image_url": "https://files.unifically.com/your-start-frame.jpg",
      "duration": 6,
      "resolution": "720p"
    }
  }'

Successful submission returns a task_id. Poll GET /v1/tasks/<task_id> or set a callback_url on the request to receive the finished video URL.