# Call Claude, GPT, Gemini and 50+ models with the OpenAI SDK

KeepRouter exposes an OpenAI-compatible endpoint at https://keeprouter.com/v1. Point the OpenAI SDK's base_url at it, keep the rest of your code, and the same calls reach 50+ models across makers — Claude, GPT, Gemini, Mistral, Qwen, Kimi, GLM, DeepSeek and more — just by changing the model id. One prepaid key, billed at cost.

## Change two things

Your existing OpenAI code stays the same except the base URL and key:

```python
from openai import OpenAI

client = OpenAI(
    base_url="https://keeprouter.com/v1",   # changed
    api_key="sk-kr-your-key",               # changed
)

r = client.chat.completions.create(
    model="claude-opus-4-8",                # now any model works
    messages=[{"role": "user", "content": "Hello"}],
)
```

Node / TypeScript is the same idea:

```ts
import OpenAI from "openai";

const client = new OpenAI({
  baseURL: "https://keeprouter.com/v1", // changed
  apiKey: process.env.KEEPROUTER_KEY,   // changed
});

const r = await client.chat.completions.create({
  model: "gemini-3.5-flash",            // swap the model id, same code
  messages: [{ role: "user", content: "Hello" }],
});
```

## One codebase, every model

Set `model` to any id from the catalog:

| Model | Maker | Price /1M (in / out) |
|---|---|---|
| `claude-opus-4-8` | Anthropic | $5.00 / $25.00 |
| `gpt-4o` | OpenAI | $2.50 / $10.00 |
| `gemini-3.5-flash` | Google DeepMind | (see catalog) |
| `deepseek-v3.2` | DeepSeek | $0.23 / $0.34 |
| `free` | — | $0 / $0 |

See every model and price on [Models & pricing](https://keeprouter.com/models.md).

## Frequently asked questions

### Do I need to change my code beyond base_url and the key?

No — the OpenAI SDK talks to KeepRouter unchanged. Just set the model id.

### Can I really call Claude with the OpenAI SDK?

Yes. KeepRouter translates between the OpenAI and Anthropic formats internally, so OpenAI-style calls reach Claude and every other model.

### Does streaming work?

Yes — pass stream=True / stream: true as usual.

### Do tool calls / function calling work?

Yes — tool calls are passed through and translated across both wire protocols.

### Which clients work?

Any OpenAI-compatible client or library — Python, Node, Go, and the many tools that accept an OpenAI base URL.

[Get an API key](https://keeprouter.com/login) · [Models & pricing](https://keeprouter.com/models.md)