What is the correct base URL for the Anthropic Claude API?
Select an answer to reveal the explanation.
Short Explanation and Infographic
api.anthropic.com — that's the official API domain. Not api.claude.ai (that's the consumer product), not api.openai.com (that's OpenAI).
Full explanation below image
Full Explanation
The Anthropic Claude API base URL is https://api.anthropic.com/v1/. The primary endpoint for creating messages is https://api.anthropic.com/v1/messages. Option A is the OpenAI API base URL — completely different company and service. Option C (claude.anthropic.com) would be for the consumer Claude.ai product, not the API. Option D (api.claude.ai) is not the correct API URL. This is fundamental knowledge for any developer integrating with Claude.