1. Get Your API Key
Sign up at the ARouter Dashboard and create an API key.
Your key will look like lr_live_xxxxxxxxxxxx.
2. Use Your Existing SDK
Pick the SDK you already use. The only changes are base_url and api_key.
Python (OpenAI)
Node.js (OpenAI)
Python (Anthropic)
cURL
from openai import OpenAI
client = OpenAI(
base_url="https://api.arouter.com/v1",
api_key="lr_live_xxxx",
)
response = client.chat.completions.create(
model="gpt-4o",
messages=[{"role": "user", "content": "Hello!"}],
)
print(response.choices[0].message.content)
import OpenAI from "openai";
const client = new OpenAI({
baseURL: "https://api.arouter.com/v1",
apiKey: "lr_live_xxxx",
});
const response = await client.chat.completions.create({
model: "gpt-4o",
messages: [{ role: "user", content: "Hello!" }],
});
console.log(response.choices[0].message.content);
import anthropic
client = anthropic.Anthropic(
base_url="https://api.arouter.com",
api_key="lr_live_xxxx",
)
message = client.messages.create(
model="claude-sonnet-4-20250514",
max_tokens=1024,
messages=[{"role": "user", "content": "Hello!"}],
)
print(message.content[0].text)
curl https://api.arouter.com/v1/chat/completions \
-H "Authorization: Bearer lr_live_xxxx" \
-H "Content-Type: application/json" \
-d '{
"model": "gpt-4o",
"messages": [{"role": "user", "content": "Hello!"}]
}'
3. Try Different Providers
With ARouter, switching providers is just changing the model string:
# OpenAI
response = client.chat.completions.create(model="openai/gpt-4o", ...)
# Anthropic (via OpenAI SDK!)
response = client.chat.completions.create(model="anthropic/claude-sonnet-4-20250514", ...)
# Google Gemini
response = client.chat.completions.create(model="google/gemini-2.0-flash", ...)
# DeepSeek
response = client.chat.completions.create(model="deepseek/deepseek-chat", ...)
If you omit the provider prefix (e.g. just "gpt-4o"), ARouter defaults to OpenAI.
What’s Next?
