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

# Claude Code

> Use Claude Code with NanoGPT and Claude + 400 models

# Claude Code

> Use Claude Code with NanoGPT to access Claude and 400+ AI models through a single API key.

<Tip>
  [Get started with NanoGPT](https://nano-gpt.com/api) for pay-as-you-go pricing with no monthly fees.
</Tip>

NanoGPT provides an Anthropic API-compatible endpoint that works seamlessly with Claude Code. This allows you to:

* Use Claude Code with your NanoGPT credits
* Access the real Claude models (Sonnet, Opus, Haiku)
* Optionally route to 400+ other models (GPT-4o, Gemini, DeepSeek, and more)

## Step 1: Install Claude Code

<Tabs>
  <Tab title="Recommended Installation Method">
    Prerequisites: [Node.js 18 or newer](https://nodejs.org/en/download/)

    ```bash theme={null}
    # Install Claude Code
    npm install -g @anthropic-ai/claude-code

    # Navigate to your project
    cd your-awesome-project

    # Start Claude Code
    claude
    ```
  </Tab>

  <Tab title="Cursor Guided Installation Method">
    If you are not familiar with npm but have Cursor, enter the command below in Cursor and it will guide you through the installation of Claude Code.

    ```
    https://docs.anthropic.com/en/docs/claude-code/overview Help me install Claude Code
    ```
  </Tab>
</Tabs>

<Note>
  **Note**: If you encounter permission issues during installation, try using `sudo` (macOS/Linux) or running the command prompt as an administrator (Windows) to re-execute the installation command.
</Note>

## Step 2: Configure NanoGPT

<Steps>
  <Step title="Get API Key">
    * Go to [NanoGPT API](https://nano-gpt.com/api)
    * Create an account or log in
    * Copy your API key
  </Step>

  <Step title="Configure Environment Variables">
    Set up environment variables using one of the following methods:

    <Tip>
      **Note**: Some commands show no output when setting environment variables. This is normal as long as no errors appear.
    </Tip>

    <Tabs>
      <Tab title="One-Click Setup (Mac/Linux)">
        Run this command in your terminal:

        ```bash theme={null}
        curl -O "https://nano-gpt.com/install/claude_code_nanogpt.sh" && bash ./claude_code_nanogpt.sh
        ```

        The script will prompt for your API key and automatically configure `~/.claude/settings.json`:

        ```json theme={null}
        {
          "env": {
            "ANTHROPIC_AUTH_TOKEN": "your_nanogpt_api_key",
            "ANTHROPIC_BASE_URL": "https://nano-gpt.com/api/v1",
            "API_TIMEOUT_MS": "600000"
          }
        }
        ```

        The installer now supports browser-based login. When the script starts, choose:

        1. Browser login (recommended) - it will open a verification URL, wait for approval, and then save your key in `~/.claude/settings.json`.
        2. Paste API key - manual fallback if you prefer.

        If a browser does not open automatically, copy the printed URL into your browser and approve the request.

        For more details on the browser login flow, see [CLI login](https://docs.nano-gpt.com/integrations/cli-login).
      </Tab>

      <Tab title="Manual Configuration (All Platforms)">
        **macOS & Linux**: Edit `~/.claude/settings.json` (create the file if it doesn't exist):

        ```json theme={null}
        {
          "env": {
            "ANTHROPIC_AUTH_TOKEN": "your_nanogpt_api_key",
            "ANTHROPIC_BASE_URL": "https://nano-gpt.com/api/v1"
          }
        }
        ```

        **Windows Cmd**:

        ```cmd theme={null}
        setx ANTHROPIC_AUTH_TOKEN your_nanogpt_api_key
        setx ANTHROPIC_BASE_URL https://nano-gpt.com/api/v1
        ```

        **Windows PowerShell**:

        ```powershell theme={null}
        [System.Environment]::SetEnvironmentVariable('ANTHROPIC_AUTH_TOKEN', 'your_nanogpt_api_key', 'User')
        [System.Environment]::SetEnvironmentVariable('ANTHROPIC_BASE_URL', 'https://nano-gpt.com/api/v1', 'User')
        ```

        Replace `your_nanogpt_api_key` with your actual API key. A new terminal window is required for changes to take effect.
      </Tab>
    </Tabs>
  </Step>
</Steps>

## Step 3: Start Using Claude Code

Once configured, start Claude Code in your terminal:

```bash theme={null}
cd your-project-directory
claude
```

> If prompted with "Do you want to use this API key," select "Yes."

Grant Claude Code permission to access files in your folder and you're ready to go.

***

## FAQ

### What Models Does This Use?

By default, Claude Code uses the real Claude models through NanoGPT:

| Claude Code Model | NanoGPT Routes To |
| ----------------- | ----------------- |
| Opus              | Claude Opus 4.5   |
| Sonnet            | Claude Sonnet 4.5 |
| Haiku             | Claude Haiku 4.5  |

No model mapping is required. NanoGPT passes the model names directly to Anthropic.

### Can I Use Other Models?

Yes. NanoGPT supports 400+ models. You can configure Claude Code to use different models by adding model mappings to your `~/.claude/settings.json`:

```json theme={null}
{
  "env": {
    "ANTHROPIC_AUTH_TOKEN": "your_nanogpt_api_key",
    "ANTHROPIC_BASE_URL": "https://nano-gpt.com/api/v1",
    "ANTHROPIC_DEFAULT_SONNET_MODEL": "openai/gpt-5.2",
    "ANTHROPIC_DEFAULT_OPUS_MODEL": "anthropic/claude-opus-4.5",
    "ANTHROPIC_DEFAULT_HAIKU_MODEL": "google/gemini-3-flash-preview"
  }
}
```

Recommended models:

| Use Case     | Recommended Model                             |
| ------------ | --------------------------------------------- |
| Best overall | `openai/gpt-5.2`, `anthropic/claude-opus-4.5` |
| Fast/cheap   | `google/gemini-3-flash-preview`               |

List available models with `GET https://nano-gpt.com/api/v1/models`.

### Configuration Not Working?

If your configuration changes don't take effect:

1. **Restart Claude Code**: Close all Claude Code windows, open a new terminal, and run `claude` again
2. **Check JSON syntax**: Ensure your `settings.json` has valid JSON (no trailing commas, proper quotes)
3. **Reset configuration**: Delete `~/.claude/settings.json` and reconfigure from scratch

### How Do I Check My Configuration?

Run `/status` inside Claude Code to see your current model configuration.

### Recommended Claude Code Version

We recommend using the latest version of Claude Code:

```bash theme={null}
# Check current version
claude --version

# Upgrade to latest
claude update
```

NanoGPT is compatible with Claude Code 1.0.0 and newer.

### How Is This Different From Using Anthropic Directly?

| Feature     | Anthropic Direct                    | NanoGPT                    |
| ----------- | ----------------------------------- | -------------------------- |
| Pricing     | Monthly subscription or API credits | Pay-as-you-go, no minimums |
| Models      | Claude only                         | Claude + 400 other models  |
| Billing     | Separate Anthropic account          | Single NanoGPT account     |
| Rate limits | Anthropic limits                    | NanoGPT limits             |

### Need Help?

* Check your balance at [nano-gpt.com/balance](https://nano-gpt.com/balance)
* View API usage at [nano-gpt.com/usage](https://nano-gpt.com/usage)
* Create or manage API keys at [nano-gpt.com/api](https://nano-gpt.com/api)
* Contact support via the chat widget on [nano-gpt.com](https://nano-gpt.com)