Claud API documentation

Claud gives you a family of fast, capable language models behind a single API that speaks the two formats your tools already understand, with transparent per-token billing and no surprise invoices.

What you get#

• One key, every model. POST /v1/chat/completions (OpenAI format) and POST /v1/messages (Anthropic format) both work with every Claud model, with streaming, tool calling, JSON output and reasoning controls.
• Drop-in compatibility. Use the OpenAI or Anthropic SDKs, Cursor, Claude Code, Continue, Open WebUI and any other tool that lets you set a base URL and an sk- key. See SDKs & libraries and Cursor, Claude Code & tools.
• Predictable billing. Requests are paid for in Claud tokens, a prepaid balance you top up with a subscription or one-off token packages. Every response tells you exactly what it cost. See Tokens & billing.
• No KYC. Sign up with an email address and pay in Bitcoin, Ethereum, USDT or USDC. There are no identity checks, no card on file and no minimum commitment.
• Usage visibility. Query your own usage, request history and balance over the API, or browse them in the dashboard.

How a request flows#

your app ──▶ https://api.claudkey.com/v1/chat/completions
              │  1. authenticate the API key and check plan limits
              │  2. reserve tokens from your balance
              │  3. route to the model (with automatic fallback if needed)
              │  4. stream the response back to you
              └▶ 5. meter the real usage and settle the reservation

Requests that fail before the model produces output are never billed. If a model is temporarily unavailable, Claud can transparently route to a fallback model of equal or greater capability; when it does, the response says so (fallback_used).

Base URL#

All API requests go to:

https://api.claudkey.com/v1

Anthropic-format clients usually append /v1/messages themselves, so configure them with https://api.claudkey.com (no /v1). Requests must use HTTPS. Plain HTTP requests are rejected.

Models at a glance#

Details, capabilities and current prices are on the Models page and are always available from GET /v1/models.

Next steps#

1. Create an account and generate an API key.
2. Follow the Quickstart to make your first request.
3. Read Streaming and Tool calling when you are ready to build.