🚅 LiteLLM

Call all LLM APIs using the OpenAI format [Bedrock, Huggingface, VertexAI, TogetherAI, Azure, OpenAI, Groq etc.]

LiteLLM Proxy Server (LLM Gateway) | Hosted Proxy (Preview) | Enterprise Tier

LiteLLM manages:

• Translate inputs to provider's completion, embedding, and image_generation endpoints
• Consistent output, text responses will always be available at ['choices'][0]['message']['content']
• Retry/fallback logic across multiple deployments (e.g. Azure/OpenAI) - Router
• Set Budgets & Rate limits per project, api key, model LiteLLM Proxy Server (LLM Gateway)

Jump to LiteLLM Proxy (LLM Gateway) Docs
Jump to Supported LLM Providers

🚨 Stable Release: Use docker images with the -stable tag. These have undergone 12 hour load tests, before being published. More information about the release cycle here

Support for more providers. Missing a provider or LLM Platform, raise a feature request.

Usage (Docs)

Important

LiteLLM v1.0.0 now requires openai>=1.0.0. Migration guide here
LiteLLM v1.40.14+ now requires pydantic>=2.0.0. No changes required.

pip install litellm

from litellm import completion
import os

## set ENV variables
os.environ["OPENAI_API_KEY"] = "your-openai-key"
os.environ["ANTHROPIC_API_KEY"] = "your-anthropic-key"

messages = [{ "content": "Hello, how are you?","role": "user"}]

# openai call
response = completion(model="openai/gpt-4o", messages=messages)

# anthropic call
response = completion(model="anthropic/claude-sonnet-4-20250514", messages=messages)
print(response)

Response (OpenAI Format)

{
    "id": "chatcmpl-1214900a-6cdd-4148-b663-b5e2f642b4de",
    "created": 1751494488,
    "model": "claude-sonnet-4-20250514",
    "object": "chat.completion",
    "system_fingerprint": null,
    "choices": [
        {
            "finish_reason": "stop",
            "index": 0,
            "message": {
                "content": "Hello! I'm doing well, thank you for asking. I'm here and ready to help with whatever you'd like to discuss or work on. How are you doing today?",
                "role": "assistant",
                "tool_calls": null,
                "function_call": null
            }
        }
    ],
    "usage": {
        "completion_tokens": 39,
        "prompt_tokens": 13,
        "total_tokens": 52,
        "completion_tokens_details": null,
        "prompt_tokens_details": {
            "audio_tokens": null,
            "cached_tokens": 0
        },
        "cache_creation_input_tokens": 0,
        "cache_read_input_tokens": 0
    }
}

Call any model supported by a provider, with model=<provider_name>/<model_name>. There might be provider-specific details here, so refer to provider docs for more information

Async (Docs)

from litellm import acompletion
import asyncio

async def test_get_response():
    user_message = "Hello, how are you?"
    messages = [{"content": user_message, "role": "user"}]
    response = await acompletion(model="openai/gpt-4o", messages=messages)
    return response

response = asyncio.run(test_get_response())
print(response)

Streaming (Docs)

liteLLM supports streaming the model response back, pass stream=True to get a streaming iterator in response.
Streaming is supported for all models (Bedrock, Huggingface, TogetherAI, Azure, OpenAI, etc.)

from litellm import completion
response = completion(model="openai/gpt-4o", messages=messages, stream=True)
for part in response:
    print(part.choices[0].delta.content or "")

# claude sonnet 4
response = completion('anthropic/claude-sonnet-4-20250514', messages, stream=True)
for part in response:
    print(part)

Response chunk (OpenAI Format)

{
    "id": "chatcmpl-fe575c37-5004-4926-ae5e-bfbc31f356ca",
    "created": 1751494808,
    "model": "claude-sonnet-4-20250514",
    "object": "chat.completion.chunk",
    "system_fingerprint": null,
    "choices": [
        {
            "finish_reason": null,
            "index": 0,
            "delta": {
                "provider_specific_fields": null,
                "content": "Hello",
                "role": "assistant",
                "function_call": null,
                "tool_calls": null,
                "audio": null
            },
            "logprobs": null
        }
    ],
    "provider_specific_fields": null,
    "stream_options": null,
    "citations": null
}

Logging Observability (Docs)

LiteLLM exposes pre defined callbacks to send data to Lunary, MLflow, Langfuse, DynamoDB, s3 Buckets, Helicone, Promptlayer, Traceloop, Athina, Slack

from litellm import completion

## set env variables for logging tools (when using MLflow, no API key set up is required)
os.environ["LUNARY_PUBLIC_KEY"] = "your-lunary-public-key"
os.environ["HELICONE_API_KEY"] = "your-helicone-auth-key"
os.environ["LANGFUSE_PUBLIC_KEY"] = ""
os.environ["LANGFUSE_SECRET_KEY"] = ""
os.environ["ATHINA_API_KEY"] = "your-athina-api-key"

os.environ["OPENAI_API_KEY"] = "your-openai-key"

# set callbacks
litellm.success_callback = ["lunary", "mlflow", "langfuse", "athina", "helicone"] # log input/output to lunary, langfuse, supabase, athina, helicone etc

#openai call
response = completion(model="openai/gpt-4o", messages=[{"role": "user", "content": "Hi 👋 - i'm openai"}])

LiteLLM Proxy Server (LLM Gateway) - (Docs)

Track spend + Load Balance across multiple projects

Hosted Proxy (Preview)

The proxy provides:

1. Hooks for auth
2. Hooks for logging
3. Cost tracking
4. Rate Limiting

📖 Proxy Endpoints - Swagger Docs

Quick Start Proxy - CLI

pip install 'litellm[proxy]'

Step 1: Start litellm proxy

$ litellm --model huggingface/bigcode/starcoder

#INFO: Proxy running on http://0.0.0.0:4000

Step 2: Make ChatCompletions Request to Proxy

Important

💡 Use LiteLLM Proxy with Langchain (Python, JS), OpenAI SDK (Python, JS) Anthropic SDK, Mistral SDK, LlamaIndex, Instructor, Curl

import openai # openai v1.0.0+
client = openai.OpenAI(api_key="anything",base_url="http://0.0.0.0:4000") # set proxy to base_url
# request sent to model set on litellm proxy, `litellm --model`
response = client.chat.completions.create(model="gpt-3.5-turbo", messages = [
    {
        "role": "user",
        "content": "this is a test request, write a short poem"
    }
])

print(response)

Proxy Key Management (Docs)

Connect the proxy with a Postgres DB to create proxy keys

# Get the code
git clone https://github.com/BerriAI/litellm

# Go to folder
cd litellm

# Add the master key - you can change this after setup
echo 'LITELLM_MASTER_KEY="sk-1234"' > .env

# Add the litellm salt key - you cannot change this after adding a model
# It is used to encrypt / decrypt your LLM API Key credentials
# We recommend - https://1password.com/password-generator/ 
# password generator to get a random hash for litellm salt key
echo 'LITELLM_SALT_KEY="sk-1234"' >> .env

source .env

# Start
docker-compose up

UI on /ui on your proxy server

Set budgets and rate limits across multiple projects POST /key/generate

Request

curl 'http://0.0.0.0:4000/key/generate' \
--header 'Authorization: Bearer sk-1234' \
--header 'Content-Type: application/json' \
--data-raw '{"models": ["gpt-3.5-turbo", "gpt-4", "claude-2"], "duration": "20m","metadata": {"user": "ishaan@berri.ai", "team": "core-infra"}}'

Expected Response

{
    "key": "sk-kdEXbIqZRwEeEiHwdg7sFA", # Bearer token
    "expires": "2023-11-19T01:38:25.838000+00:00" # datetime object
}

Supported Providers (Docs)

Provider	Completion	Streaming	Async Completion	Async Streaming	Async Embedding	Async Image Generation
openai	✅	✅	✅	✅	✅	✅
Meta - Llama API	✅	✅	✅	✅
azure	✅	✅	✅	✅	✅	✅
AI/ML API	✅	✅	✅	✅	✅	✅
aws - sagemaker	✅	✅	✅	✅	✅
aws - bedrock	✅	✅	✅	✅	✅
google - vertex_ai	✅	✅	✅	✅	✅	✅
google - palm	✅	✅	✅	✅
google AI Studio - gemini	✅	✅	✅	✅
mistral ai api	✅	✅	✅	✅	✅
cloudflare AI Workers	✅	✅	✅	✅
cohere	✅	✅	✅	✅	✅
anthropic	✅	✅	✅	✅
empower	✅	✅	✅	✅
huggingface	✅	✅	✅	✅	✅
replicate	✅	✅	✅	✅
together_ai	✅	✅	✅	✅
openrouter	✅	✅	✅	✅
ai21	✅	✅	✅	✅
baseten	✅	✅	✅	✅
vllm	✅	✅	✅	✅
nlp_cloud	✅	✅	✅	✅
aleph alpha	✅	✅	✅	✅
petals	✅	✅	✅	✅
ollama	✅	✅	✅	✅	✅
deepinfra	✅	✅	✅	✅
perplexity-ai	✅	✅	✅	✅
Groq AI	✅	✅	✅	✅
Deepseek	✅	✅	✅	✅
anyscale	✅	✅	✅	✅
IBM - watsonx.ai	✅	✅	✅	✅	✅
voyage ai					✅
xinference [Xorbits Inference]					✅
FriendliAI	✅	✅	✅	✅
Galadriel	✅	✅	✅	✅
Novita AI	✅	✅	✅	✅
Featherless AI	✅	✅	✅	✅
Nebius AI Studio	✅	✅	✅	✅	✅

Read the Docs

Contributing

Interested in contributing? Contributions to LiteLLM Python SDK, Proxy Server, and LLM integrations are both accepted and highly encouraged!

Quick start: git clone → make install-dev → make format → make lint → make test-unit

See our comprehensive Contributing Guide (CONTRIBUTING.md) for detailed instructions.

Enterprise

For companies that need better security, user management and professional support

Talk to founders

This covers:

• ✅ Features under the LiteLLM Commercial License:
• ✅ Feature Prioritization
• ✅ Custom Integrations
• ✅ Professional Support - Dedicated discord + slack
• ✅ Custom SLAs
• ✅ Secure access with Single Sign-On

Contributing

We welcome contributions to LiteLLM! Whether you're fixing bugs, adding features, or improving documentation, we appreciate your help.

Quick Start for Contributors

git clone https://github.com/BerriAI/litellm.git
cd litellm
make install-dev    # Install development dependencies
make format         # Format your code
make lint           # Run all linting checks
make test-unit      # Run unit tests

For detailed contributing guidelines, see CONTRIBUTING.md.

Code Quality / Linting

LiteLLM follows the Google Python Style Guide.

Our automated checks include:

• Black for code formatting
• Ruff for linting and code quality
• MyPy for type checking
• Circular import detection
• Import safety checks

Run all checks locally:

make lint           # Run all linting (matches CI)
make format-check   # Check formatting only

All these checks must pass before your PR can be merged.

Support / talk with founders

• Schedule Demo 👋
• Community Discord 💭
• Community Slack 💭
• Our numbers 📞 +1 (770) 8783-106 / ‭+1 (412) 618-6238‬
• Our emails ✉️ ishaan@berri.ai / krrish@berri.ai

Why did we build this

• Need for simplicity: Our code started to get extremely complicated managing & translating calls between Azure, OpenAI and Cohere.

Contributors

Run in Developer mode

Services

1. Setup .env file in root
2. Run dependant services docker-compose up db prometheus

Backend

1. (In root) create virtual environment python -m venv .venv
2. Activate virtual environment source .venv/bin/activate
3. Install dependencies pip install -e ".[all]"
4. Start proxy backend uvicorn litellm.proxy.proxy_server:app --host localhost --port 4000 --reload

Frontend

1. Navigate to ui/litellm-dashboard
2. Install dependencies npm install
3. Run npm run dev to start the dashboard