These examples use the website API host, which currently lists their recommended models. The direct API host can have a different catalog during rollouts. For larger requests or longer runtimes, use https://api.nano-gpt.com/api/v1 with a model from that host’s catalog. See API Hosts for limits and availability checks.

Claude Code

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

Get started with NanoGPT for pay-as-you-go pricing with no monthly fees.

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

Recommended Installation Method
Cursor Guided Installation Method

Prerequisites: Node.js 18 or newer

# Install Claude Code
npm install -g @anthropic-ai/claude-code

# Navigate to your project
cd your-awesome-project

# Start Claude Code
claude

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

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.

Step 2: Configure NanoGPT

Get API Key

Go to NanoGPT API
Create an account or log in
Copy your API key

Configure Environment Variables

Set up environment variables using one of the following methods:

Note: Some commands show no output when setting environment variables. This is normal as long as no errors appear.

One-Click Setup (Mac/Linux)
Manual Configuration (All Platforms)

Run this command in your terminal:

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:

{
  "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:

Browser login (recommended) - it will open a verification URL, wait for approval, and then save your key in ~/.claude/settings.json.
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.

macOS & Linux: Edit ~/.claude/settings.json (create the file if it doesn’t exist):

{
  "env": {
    "ANTHROPIC_AUTH_TOKEN": "your_nanogpt_api_key",
    "ANTHROPIC_BASE_URL": "https://nano-gpt.com/api/v1"
  }
}

Windows Cmd:

setx ANTHROPIC_AUTH_TOKEN your_nanogpt_api_key
setx ANTHROPIC_BASE_URL https://nano-gpt.com/api/v1

Windows PowerShell:

[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.

Step 3: Start Using Claude Code

Once configured, start Claude Code in your terminal:

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?

Claude Code sends its selected model ID to NanoGPT. To choose our current Claude recommendations explicitly, add these variables to the env section of ~/.claude/settings.json:

{
  "ANTHROPIC_DEFAULT_OPUS_MODEL": "anthropic/claude-opus-5.5",
  "ANTHROPIC_DEFAULT_SONNET_MODEL": "anthropic/claude-sonnet-5.5",
  "ANTHROPIC_DEFAULT_HAIKU_MODEL": "anthropic/claude-haiku-latest"
}

Claude Code Model	NanoGPT Routes To
Opus	Claude Opus 5.5
Sonnet	Claude Sonnet 5.5
Haiku	Claude Haiku 4.5 Thinking

These settings select the public NanoGPT model IDs shown above. Existing Claude Code configurations can continue to use older releases.

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:

{
  "env": {
    "ANTHROPIC_AUTH_TOKEN": "your_nanogpt_api_key",
    "ANTHROPIC_BASE_URL": "https://nano-gpt.com/api/v1",
    "ANTHROPIC_DEFAULT_SONNET_MODEL": "openai/gpt-6.1-sol",
    "ANTHROPIC_DEFAULT_OPUS_MODEL": "anthropic/claude-opus-5.5",
    "ANTHROPIC_DEFAULT_HAIKU_MODEL": "google/gemini-flash-latest"
  }
}

Recommended models:

Use Case	Recommended Model
Best overall	`openai/gpt-6.1-sol`, `anthropic/claude-opus-5.5`
Fast/cheap	`google/gemini-flash-latest`

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

Configuration Not Working?

If your configuration changes don’t take effect:

Restart Claude Code: Close all Claude Code windows, open a new terminal, and run claude again
Check JSON syntax: Ensure your settings.json has valid JSON (no trailing commas, proper quotes)
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:

# 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
View API usage at nano-gpt.com/usage
Create or manage API keys at nano-gpt.com/api
Contact support via the chat widget on nano-gpt.com

Get Started

Endpoint Examples

API Reference

Miscellaneous

Partner

Integrations

Claude Code

Claude Code

Step 1: Install Claude Code

Step 2: Configure NanoGPT

Step 3: Start Using Claude Code

FAQ

What Models Does This Use?

Can I Use Other Models?

Configuration Not Working?

How Do I Check My Configuration?

Recommended Claude Code Version

How Is This Different From Using Anthropic Directly?

Need Help?

​Claude Code

​Step 1: Install Claude Code

​Step 2: Configure NanoGPT

​Step 3: Start Using Claude Code

​FAQ

​What Models Does This Use?

​Can I Use Other Models?

​Configuration Not Working?

​How Do I Check My Configuration?

​Recommended Claude Code Version

​How Is This Different From Using Anthropic Directly?

​Need Help?

Claude Code

Step 1: Install Claude Code

Step 2: Configure NanoGPT

Step 3: Start Using Claude Code

FAQ

What Models Does This Use?

Can I Use Other Models?

Configuration Not Working?

How Do I Check My Configuration?

Recommended Claude Code Version

How Is This Different From Using Anthropic Directly?

Need Help?