---
title: "Black Forest Labs Image Generation"
description: "import Tabs from '@theme/Tabs'; import TabItem from '@theme/TabItem';"
type: skill
canonical_url: https://claudary.paisolsolutions.com/skills/black-forest-labs
source: "Claudary"
difficulty: intermediate
author: "Claude Code Knowledge Pack"
date: 2026-07-10T11:08:27.776Z
license: CC-BY-4.0
attribution: "Black Forest Labs Image Generation — Claudary (https://claudary.paisolsolutions.com/skills/black-forest-labs)"
---

# Black Forest Labs Image Generation
import Tabs from '@theme/Tabs'; import TabItem from '@theme/TabItem';

## Overview

import Tabs from '@theme/Tabs';
import TabItem from '@theme/TabItem';

# Black Forest Labs Image Generation

Black Forest Labs provides state-of-the-art text-to-image generation using their FLUX models.

## Overview

| Property | Details |
|----------|---------|
| Description | Black Forest Labs FLUX models for high-quality text-to-image generation |
| Provider Route on LiteLLM | `black_forest_labs/` |
| Provider Doc | [Black Forest Labs API ↗](https://docs.bfl.ai/) |
| Supported Operations | [`/images/generations`](#image-generation) |

## Setup

### API Key

```python showLineNumbers
import os

# Set your Black Forest Labs API key
os.environ["BFL_API_KEY"] = "your-api-key-here"
```

Get your API key from [Black Forest Labs](https://blackforestlabs.ai/).

## Supported Models

| Model Name | Description | Price |
|------------|-------------|-------|
| `black_forest_labs/flux-pro-1.1` | Fast & reliable standard generation | $0.04/image |
| `black_forest_labs/flux-pro-1.1-ultra` | Ultra high-resolution (up to 4MP) | $0.06/image |
| `black_forest_labs/flux-dev` | Development/open-source variant | $0.025/image |
| `black_forest_labs/flux-pro` | Original pro model | $0.05/image |

## Image Generation

### Usage - LiteLLM Python SDK

<Tabs>
<TabItem value="basic" label="Basic Usage">

```python showLineNumbers title="Basic Image Generation"
import os
import litellm

# Set your API key
os.environ["BFL_API_KEY"] = "your-api-key-here"

# Generate an image
response = litellm.image_generation(
    model="black_forest_labs/flux-pro-1.1",
    prompt="A beautiful sunset over the ocean with sailing boats",
)

# BFL returns URLs
print(response.data[0].url)
```

</TabItem>

<TabItem value="async" label="Async Usage">

```python showLineNumbers title="Async Image Generation"
import os
import asyncio
import litellm

# Set your API key
os.environ["BFL_API_KEY"] = "your-api-key-here"

async def generate_image():
    response = await litellm.aimage_generation(
        model="black_forest_labs/flux-pro-1.1",
        prompt="A futuristic city skyline at night",
    )
    print(response.data[0].url)

# Run the async function
asyncio.run(generate_image())
```

</TabItem>

<TabItem value="size" label="Custom Size">

```python showLineNumbers title="Image Generation with Custom Size"
import os
import litellm

# Set your API key
os.environ["BFL_API_KEY"] = "your-api-key-here"

# Generate with specific dimensions
response = litellm.image_generation(
    model="black_forest_labs/flux-pro-1.1",
    prompt="A majestic mountain landscape",
    size="1792x1024",  # Maps to width/height
)

print(response.data[0].url)
```

</TabItem>

<TabItem value="ultra" label="Ultra High-Res">

```python showLineNumbers title="Ultra High Resolution with flux-pro-1.1-ultra"
import os
import litellm

# Set your API key
os.environ["BFL_API_KEY"] = "your-api-key-here"

# Generate ultra high-resolution image
response = litellm.image_generation(
    model="black_forest_labs/flux-pro-1.1-ultra",
    prompt="Detailed portrait of a fantasy character",
    size="2048x2048",    # Up to 4MP supported
    quality="hd",        # Maps to raw=True for natural look
)

print(response.data[0].url)
```

</TabItem>

<TabItem value="advanced" label="Advanced Parameters">

```python showLineNumbers title="Advanced Image Generation with BFL Parameters"
import os
import litellm

# Set your API key
os.environ["BFL_API_KEY"] = "your-api-key-here"

# Generate with BFL-specific parameters
response = litellm.image_generation(
    model="black_forest_labs/flux-pro-1.1",
    prompt="A cute orange cat sitting on a windowsill",
    seed=42,                    # For reproducible results
    output_format="png",        # png or jpeg
    safety_tolerance=2,         # 0-6, higher = more permissive
    prompt_upsampling=True,     # Enhance prompt for better results
)

print(response.data[0].url)
```

</TabItem>
</Tabs>

### Usage - LiteLLM Proxy Server

#### 1. Configure your config.yaml

```yaml showLineNumbers title="Black Forest Labs Image Generation Configuration"
model_list:
  - model_name: flux-pro
    litellm_params:
      model: black_forest_labs/flux-pro-1.1
      api_key: os.environ/BFL_API_KEY
    model_info:
      mode: image_generation

  - model_name: flux-ultra
    litellm_params:
      model: black_forest_labs/flux-pro-1.1-ultra
      api_key: os.environ/BFL_API_KEY
    model_info:
      mode: image_generation

  - model_name: flux-dev
    litellm_params:
      model: black_forest_labs/flux-dev
      api_key: os.environ/BFL_API_KEY
    model_info:
      mode: image_generation

general_settings:
  master_key: sk-1234
```

#### 2. Start LiteLLM Proxy Server

```bash showLineNumbers title="Start LiteLLM Proxy Server"
litellm --config /path/to/config.yaml

# RUNNING on http://0.0.0.0:4000
```

#### 3. Make image generation requests

<Tabs>
<TabItem value="openai-sdk" label="OpenAI SDK">

```python showLineNumbers title="Black Forest Labs via Proxy - OpenAI SDK"
from openai import OpenAI

# Initialize client with your proxy URL
client = OpenAI(
    base_url="http://localhost:4000",
    api_key="sk-1234"
)

# Generate image with FLUX Pro
response = client.images.generate(
    model="flux-pro",
    prompt="A beautiful garden with colorful flowers",
    size="1024x1024",
)

print(response.data[0].url)
```

</TabItem>

<TabItem value="curl" label="cURL">

```bash showLineNumbers title="Black Forest Labs via Proxy - cURL"
curl -X POST 'http://localhost:4000/v1/images/generations' \\
  -H 'Content-Type: application/json' \\
  -H 'Authorization: Bearer sk-1234' \\
  -d '{
    "model": "flux-pro",
    "prompt": "A beautiful garden with colorful flowers",
    "size": "1024x1024"
  }'
```

</TabItem>
</Tabs>

## Supported Parameters

### OpenAI-Compatible Parameters

| Parameter | Type | Description | Mapping |
|-----------|------|-------------|---------|
| `prompt` | string | Text description of the image to generate | Direct |
| `model` | string | The FLUX model to use | Direct |
| `size` | string | Image dimensions (e.g., `1024x1024`) | Maps to `width` and `height` |
| `n` | integer | Number of images (ultra model only, up to 4) | Maps to `num_images` |
| `quality` | string | `hd` for natural look | Maps to `raw=True` for ultra |
| `response_format` | string | `url` or `b64_json` | Direct |

### Black Forest Labs Specific Parameters

| Parameter | Type | Description | Default |
|-----------|------|-------------|---------|
| `width` | integer | Image width (256-1920, multiples of 16) | 1024 |
| `height` | integer | Image height (256-1920, multiples of 16) | 1024 |
| `aspect_ratio` | string | Alternative to width/height (e.g., `16:9`, `1:1`) | - |
| `seed` | integer | Seed for reproducible results | Random |
| `output_format` | string | Output format: `png` or `jpeg` | `png` |
| `safety_tolerance` | integer | Safety filter tolerance (0-6, higher = more permissive) | 2 |
| `prompt_upsampling` | boolean | Enhance prompt for better results | `false` |

### Ultra Model Specific Parameters

| Parameter | Type | Description | Default |
|-----------|------|-------------|---------|
| `raw` | boolean | Raw mode for more natural, less synthetic look | `false` |
| `num_images` | integer | Number of images to generate (1-4) | 1 |

## How It Works

Black Forest Labs uses a polling-based API:

1. **Submit Request**: LiteLLM sends your prompt to BFL
2. **Get Task ID**: BFL returns a task ID and polling URL
3. **Poll for Result**: LiteLLM automatically polls until the image is ready
4. **Return Result**: The generated image URL is returned

This polling is handled automatically by LiteLLM - you just call `image_generation()` and get the result.

## Getting Started

1. Create an account at [Black Forest Labs](https://blackforestlabs.ai/)
2. Get your API key from the dashboard
3. Set your `BFL_API_KEY` environment variable
4. Use `litellm.image_generation()` with any supported model

## Additional Resources

- [Black Forest Labs Documentation](https://docs.bfl.ai/)
- [Black Forest Labs Image Editing](./black_forest_labs_img_edit.md) - For editing existing images
- [FLUX Model Information](https://blackforestlabs.ai/)

---

Source: [Claudary](https://claudary.paisolsolutions.com/skills/black-forest-labs) · https://claudary.paisolsolutions.com