How to Use Claude Code, Cursor & Codex for Free
Free alternative to paid Anthropic and OpenAI APIs. Pick a tool, pick a free LLM backend, copy the config — done in 30 seconds.
Claude Code, Cursor, Codex, and Gemini CLI all accept custom API endpoints via environment variables like
ANTHROPIC_BASE_URL or OPENAI_BASE_URL. That means you can swap the paid official API
for a free, OpenAI-compatible backend — NVIDIA NIM, OpenRouter, Groq, Cerebras, Mistral — without changing
a single line of code. This generator produces the exact config snippet for each tool + backend combination.
No credit card required.
1. Pick your tool
2. Pick your free backend
Select a tool above to see compatible free backends.
Frequently Asked Questions
How do I use Claude Code for free?
Set ANTHROPIC_BASE_URL to an OpenAI-compatible free backend (NVIDIA NIM, OpenRouter, Groq) and ANTHROPIC_AUTH_TOKEN to that provider's API key. See the Claude Code config for copy-paste snippets.
Is there a free alternative to OpenAI API?
Yes. Groq, NVIDIA NIM, OpenRouter, Mistral, Cerebras, Cohere, and Cloudflare Workers AI all offer OpenAI-compatible APIs for free. Just swap OPENAI_BASE_URL and OPENAI_API_KEY — your existing code keeps working.
Can I use Cursor with a free API key?
Yes. In Cursor Settings → Models → Add Model, enter a free provider's base URL (e.g. https://api.groq.com/openai/v1) and your free API key. See the Cursor config for the exact model names to add.
Which free backend works best with Claude Code?
For speed: Groq (Llama 3.3 70B). For long context: Google AI Studio (Gemini 2.5 Flash, 1M tokens). For model variety: NVIDIA NIM (100+ models including DeepSeek R1). For everything via one key: OpenRouter.
Do I need to install anything?
No. Just copy the generated environment variables into your shell config (~/.zshrc or ~/.bashrc) and restart your tool. No proxy server, no local deployment.