Fal AI

Fal AI provides fast, scalable access to state-of-the-art image generation models including FLUX, Stable Diffusion, Imagen, and more.

Overview

Setup

API Key

# Set your Fal AI API key
os.environ["FAL_AI_API_KEY"] = "your-fal-api-key"

Get your API key from fal.ai.

Supported Models

Image Generation

Usage - LiteLLM Python SDK

# Set your API key
os.environ["FAL_AI_API_KEY"] = "your-fal-api-key"

# Generate an image
response = litellm.image_generation(
    model="fal_ai/fal-ai/flux-pro/v1.1-ultra",
    prompt="A serene mountain landscape at sunset with vibrant colors"
)

print(response.data[0].url)

os.environ["FAL_AI_API_KEY"] = "your-fal-api-key"

# Generate with Imagen 4
response = litellm.image_generation(
    model="fal_ai/fal-ai/imagen4/preview",
    prompt="A vintage 1960s kitchen with flour package on countertop",
    aspect_ratio="16:9",
    num_images=1
)

print(response.data[0].url)

os.environ["FAL_AI_API_KEY"] = "your-fal-api-key"

# Generate with specific style
response = litellm.image_generation(
    model="fal_ai/fal-ai/recraft/v3/text-to-image",
    prompt="A red panda eating bamboo",
    style="realistic_image",
    image_size="landscape_4_3"
)

print(response.data[0].url)

async def generate_image():
    os.environ["FAL_AI_API_KEY"] = "your-fal-api-key"
    
    response = await litellm.aimage_generation(
        model="fal_ai/fal-ai/stable-diffusion-v35-medium",
        prompt="A cyberpunk cityscape with neon lights",
        guidance_scale=7.5,
        num_inference_steps=50
    )
    
    print(response.data[0].url)
    return response

asyncio.run(generate_image())

os.environ["FAL_AI_API_KEY"] = "your-fal-api-key"

# Generate with advanced parameters
response = litellm.image_generation(
    model="fal_ai/fal-ai/flux-pro/v1.1-ultra",
    prompt="A majestic dragon soaring over mountains",
    n=2,
    size="1792x1024",  # Maps to aspect_ratio="16:9"
    seed=42,
    safety_tolerance="2",
    enhance_prompt=True
)

for image in response.data:
    print(f"Generated image: {image.url}")

Usage - LiteLLM Proxy Server

1. Configure your config.yaml

model_list:
  - model_name: flux-ultra
    litellm_params:
      model: fal_ai/fal-ai/flux-pro/v1.1-ultra
      api_key: os.environ/FAL_AI_API_KEY
    model_info:
      mode: image_generation
  
  - model_name: imagen4
    litellm_params:
      model: fal_ai/fal-ai/imagen4/preview
      api_key: os.environ/FAL_AI_API_KEY
    model_info:
      mode: image_generation
  
  - model_name: stable-diffusion
    litellm_params:
      model: fal_ai/fal-ai/stable-diffusion-v35-medium
      api_key: os.environ/FAL_AI_API_KEY
    model_info:
      mode: image_generation

general_settings:
  master_key: sk-1234

2. Start LiteLLM Proxy Server

litellm --config /path/to/config.yaml

# RUNNING on http://0.0.0.0:4000

3. Make requests

from openai import OpenAI

client = OpenAI(
    base_url="http://localhost:4000",
    api_key="sk-1234"
)

response = client.images.generate(
    model="flux-ultra",
    prompt="A beautiful sunset over the ocean",
    n=1,
    size="1024x1024"
)

print(response.data[0].url)

response = litellm.image_generation(
    model="litellm_proxy/imagen4",
    prompt="A cozy coffee shop interior",
    api_base="http://localhost:4000",
    api_key="sk-1234"
)

print(response.data[0].url)

curl --location 'http://localhost:4000/v1/images/generations' \\
--header 'Content-Type: application/json' \\
--header 'Authorization: Bearer sk-1234' \\
--data '{
    "model": "stable-diffusion",
    "prompt": "A serene Japanese garden with cherry blossoms",
    "n": 1,
    "size": "1024x1024"
}'

Using Model-Specific Parameters

LiteLLM forwards any additional parameters directly to the Fal AI API. You can pass model-specific parameters in your request and they will be sent to Fal AI.

# Any parameters beyond the standard ones are forwarded to Fal AI
response = litellm.image_generation(
    model="fal_ai/fal-ai/flux-pro/v1.1-ultra",
    prompt="A beautiful sunset",
    # Model-specific Fal AI parameters
    aspect_ratio="16:9",
    safety_tolerance="2",
    enhance_prompt=True,
    seed=42
)

For the complete list of parameters supported by each model, see:

• FLUX Pro v1.1-ultra Parameters ↗
• Imagen 4 Parameters ↗
• Recraft v3 Parameters ↗
• Stable Diffusion v3.5 Parameters ↗
• Bria 3.2 Parameters ↗

Supported Parameters

Standard OpenAI-compatible parameters that work across all models:

Getting Started

1. Sign up at fal.ai
2. Get your API key from your account settings
3. Set FAL_AI_API_KEY environment variable
4. Choose a model from the Fal AI model gallery
5. Start generating images with LiteLLM

Additional Resources

• Fal AI Documentation
• Model Gallery
• API Reference
• Pricing