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

# FLUX 3 Image

> Black Forest Labs' full FLUX 3 image model: text-to-image, editing, bounding-box layouts, up to 10 references and web grounding up to 4K. See parameters, response fields, and API examples.

Generate and edit images with FLUX 3 Image, the full FLUX 3 image model from Black Forest Labs. One route covers text-to-image, image editing and multi-reference generation with up to 10 reference images, and the prompt can carry bounding boxes that place each element.

Try it in the browser: [FLUX 3 Image API playground](https://unifically.com/models/flux-3-image).

## Model

```
black-forest-labs/flux-3-image
```

## Parameters

| Parameter | Type | Required | Default | Description |
| - | - | - | - | - |
| `prompt` | string | Yes | - | Text description of the image or the edit to apply. May end with a bounding-box element table (see below) |
| `image_urls` | string\[] | No | `[]` | 0-10 reference image URLs for editing or multi-reference generation. Refer to them in the prompt as image 1, image 2, ... |
| `aspect_ratio` | string | No | `"auto"` | `"auto"`, `"21:9"`, `"2:1"`, `"16:9"`, `"3:2"`, `"7:5"`, `"4:3"`, `"5:4"`, `"1:1"`, `"4:5"`, `"3:4"`, `"5:7"`, `"2:3"`, `"9:16"`, `"1:2"`, `"9:21"`. With `auto` the prompt decides, or the first reference image's framing when one is attached |
| `resolution` | string | No | `"1k"` | `"768sq"`, `"1k"`, `"1.5k"`, `"2k"`, `"4k"` (case-insensitive). Each is a fixed pixel area; exact dimensions follow the aspect ratio |
| `grounding` | boolean | No | `true` | Research the prompt with web and image search before generating. Set `false` for faster runs that use only the prompt |

> [!NOTE]
>
> FLUX 3 Image has no `seed`, `steps`, `guidance` or `negative_prompt`. Output is a single JPG image.

## Bounding boxes

Append a JSON array to the prompt, one row per element, and tag each element in the caption with its id (`<cabin_1>`). Each `bbox` is `[top, left, bottom, right]` on a 0 to 1000 grid at any aspect ratio.

```text theme={null}
A small black timber cabin <cabin_1> on a snowy slope, with the headline <headline_1> in the sky above it. [{"id": "headline_1", "bbox": [60, 60, 230, 640], "desc": "\"QUIET PLACES\" in a tall black serif typeface"}, {"id": "cabin_1", "bbox": [420, 250, 800, 620], "desc": "a small black timber cabin with a glowing window"}]
```

## Example Request

```bash theme={null}
curl -X POST https://api.unifically.com/v1/tasks   -H "Content-Type: application/json"   -H "Authorization: Bearer YOUR_API_KEY"   -d '{
    "model": "black-forest-labs/flux-3-image",
    "input": {
      "prompt": "A screen-printed concert poster with the headline \"BLUE HOUR SESSIONS\" above an upright bass player on cobalt blue",
      "aspect_ratio": "2:3",
      "resolution": "1k",
      "grounding": false
    }
  }'
```

Multi-reference generation:

```bash theme={null}
curl -X POST https://api.unifically.com/v1/tasks   -H "Content-Type: application/json"   -H "Authorization: Bearer YOUR_API_KEY"   -d '{
    "model": "black-forest-labs/flux-3-image",
    "input": {
      "prompt": "The woman from image 1 inspects the watch movement from image 2 at a watchmaker bench",
      "image_urls": ["https://example.com/portrait.jpg", "https://example.com/movement.jpg"],
      "resolution": "2k"
    }
  }'
```

## Response

```json theme={null}
{
  "code": 200,
  "success": true,
  "data": {
    "task_id": "abc123def456",
    "status": "processing"
  }
}
```

Poll `GET /v1/tasks/<task_id>` or set a `callback_url` to receive the finished image URL.

> [!NOTE]
>
> **Volume discounts** are available for almost all models. Reach out at [contact@unifically.com](mailto:contact@unifically.com) to discuss custom pricing.


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