> ## Documentation Index
> Fetch the complete documentation index at: https://docs.helicone.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# OpenRouter Integration

> Integrate Helicone with OpenRouter, a unified API for accessing multiple LLM providers. Monitor and analyze AI interactions across various models through a single, streamlined interface.

<Warning>
  This integration method is maintained but no longer actively developed. For the best experience and latest features, use our new [AI Gateway](/gateway/overview) with unified API access to 100+ models.
</Warning>

[OpenRouter](https://openrouter.ai/) is a tool that helps you integrate multiple NLP APIs in your application. It provides a single API endpoint that you can use to call multiple NLP APIs.

You can follow their documentation here: [https://openrouter.ai/docs#quick-start](https://openrouter.ai/docs#quick-start)

# Gateway Integration

<Steps>
  <Step title="Create a Helicone account">
    Log into [helicone](https://www.helicone.ai) or create an account. Once you have an account, you
    can generate an [API key](https://helicone.ai/developer).
  </Step>

  <Step title="Create an OpenRouter account">
    Log into [www.openrouter.ai](http://www.openrouter.ai) or create an account. Once you have an account, you
    can generate an [API key](https://openrouter.ai/docs#api-keys).
  </Step>

  <Step title="Set HELICONE_API_KEY and OPENROUTER_API_KEY as environment variable">
    ```javascript theme={null}
    HELICONE_API_KEY=<your API key>
    OPENROUTER_API_KEY=<your API key>
    ```
  </Step>

  <Step title="Modify the base URL and add Auth headers">
    Replace the following OpenRouter URL with the Helicone Gateway URL:

    `https://openrouter.ai/api/v1/chat/completions` -> `https://openrouter.helicone.ai/api/v1/chat/completions`

    and then add the following authentication headers.

    ```
    Helicone-Auth: `Bearer ${HELICONE_API_KEY}`
    Authorization: `Bearer ${OPENROUTER_API_KEY}`
    ```
  </Step>
</Steps>

Now you can access all the models on OpenRouter with a simple fetch call:

## Example

```typescript theme={null}
fetch("https://openrouter.helicone.ai/api/v1/chat/completions", {
  method: "POST",
  headers: {
    Authorization: `Bearer ${OPENROUTER_API_KEY}`,
    "Helicone-Auth": `Bearer ${HELICONE_API_KEY}`,
    "HTTP-Referer": `${YOUR_SITE_URL}`, // Optional, for including your app on openrouter.ai rankings.
    "X-Title": `${YOUR_SITE_NAME}`, // Optional. Shows in rankings on openrouter.ai.
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    model: "openai/gpt-4o-mini", // Optional (user controls the default),
    messages: [{ role: "user", content: "What is the meaning of life?" }],
    stream: true,
  }),
});
```

We now also support streaming in responses from OpenRouter.

<Info>
  **Note:** usage data and cost calculations *while streaming* are only offered
  for OpenAI and Anthropic models. For non-stream requests, usage data and cost
  calculations are available for all models.
</Info>

For more information on how to use headers, see [Helicone Headers](https://docs.helicone.ai/helicone-headers/header-directory#utilizing-headers) docs.
And for more information on how to use OpenRouter, see [OpenRouter Docs](https://openrouter.ai/docs).