# Free API — pricing & specs

A free, no-cost model on KeepRouter, priced at $0 per token. It's meant for testing, prototyping, and evaluating the OpenAI- and Anthropic-compatible API before moving to a paid model — call it by setting the model to "free". As a free tier it's best-effort, so use a paid model for production traffic. On KeepRouter, Free is free — you pay $0 per token, with no monthly fee. Call it through the OpenAI- or Anthropic-compatible API with the model id `free`.

| Spec | Value |
|---|---|
| Modality | Text |
| Input price | $0 per 1M tokens |
| Output price | $0 per 1M tokens |
| Capabilities | Streaming, Tool / function calling |
| APIs | OpenAI-compatible, Anthropic-compatible |
| Model id | `free` |

## Call it via the OpenAI API (cURL)

```bash
curl https://keeprouter.com/v1/chat/completions \
  -H "Authorization: Bearer $KEEPROUTER_KEY" -H "Content-Type: application/json" \
  -d '{"model":"free","messages":[{"role":"user","content":"Hello"}]}'
```

## Python

```python
from openai import OpenAI
client = OpenAI(base_url="https://keeprouter.com/v1", api_key="$KEEPROUTER_KEY")
r = client.chat.completions.create(model="free", messages=[{"role":"user","content":"Hello"}])
```

## JavaScript

```js
import OpenAI from "openai";
const client = new OpenAI({ baseURL: "https://keeprouter.com/v1", apiKey: process.env.KEEPROUTER_KEY });
const r = await client.chat.completions.create({ model: "free", messages: [{ role: "user", content: "Hello" }] });
```

## Frequently asked questions

### How much does Free cost on KeepRouter?

Free is free — you pay $0 per token, with no monthly fee. It's best-effort, for testing and prototyping.

### How do I call Free via API?

Point your OpenAI- or Anthropic-compatible client at KeepRouter and set the model to "free". It works with the OpenAI SDK, the Anthropic SDK, and Claude Code — no provider-specific SDK needed.

### Does Free support streaming?

Yes. KeepRouter streams Free responses over both the OpenAI and Anthropic APIs.

### Does Free support tool (function) calling?

Yes. KeepRouter passes tool calls through to Free and translates them between the OpenAI and Anthropic formats.

## Guides

- [Call Free with the OpenAI SDK](https://keeprouter.com/use-cases/openai-sdk.md)
- [Use Free in Claude Code](https://keeprouter.com/use-cases/claude-code.md)

## More

- [All models & pricing](https://keeprouter.com/models.md)
- [Quickstart](https://keeprouter.com/docs/quickstart.md)
- [Get an API key](https://keeprouter.com/login)

_Prices as of 2026-07-05._