How to Use Claude API Key in Cursor IDE
Complete guide to setting up your Claude API key in Cursor IDE. Connect to Claude Sonnet, Opus, and Haiku models directly from your code editor.
Why Use Claude in Cursor?
Cursor is the leading AI-powered code editor, and connecting it to Claude models gives you access to some of the most capable coding assistants available. With a ClaudeStore API key, you can use Claude Sonnet 4.6, Opus 4.6, and Haiku 4.5 directly inside Cursor — no Anthropic account required.
This setup takes less than 2 minutes and works with all Cursor features: Tab completion, Chat, Composer, and inline edits.
Step-by-Step Setup
1. Get Your API Key
If you don't have a ClaudeStore API key yet, follow our guide to get one. It takes under a minute.
2. Open Cursor Settings
In Cursor, open Settings (Cmd/Ctrl + ,) and navigate to Models → Model Configuration.
3. Configure the API Endpoint
Cursor uses the OpenAI-compatible mode. Set the following values:
- OpenAI Base URL:
https://api2.claudestore.store/v1(must include/v1) - API Key: Your ClaudeStore API key
https://api2.claudestore.store without /v1. Cursor uses the OpenAI-compatible endpoint with /v1.4. Select a Model
Choose from available Claude models:
- claude-sonnet-4.6 — Best balance of speed and quality
- claude-opus-4.6 — Maximum capability for complex tasks
- claude-haiku-4.5 — Fast and cost-efficient
5. Verify the Connection
Open Cursor Chat (Cmd/Ctrl + L) and send a test message. You should see a response from Claude within seconds.
Troubleshooting
'Invalid API Key' Error
Double-check that you copied the full key including the sk- prefix. Keys are shown only once — if lost, generate a new one from your dashboard.
'Model not found' Error
Ensure you're using the exact model ID (e.g., claude-sonnet-4.6). Check our Models page for the full list.
Slow Responses
If responses are slow, try switching to Haiku for faster completions or check if prompt caching is enabled. See Pricing Explained for caching details.
Tips for Power Users
- Use Sonnet for daily coding — it's the best price/performance ratio
- Switch to Opus for complex refactors or architecture decisions
- Set per-key credit limits in your ClaudeStore dashboard to control costs
- Use the OpenAI-compatible endpoint for seamless Cursor integration