About Claude Opus 5
Claude Opus 5 by Anthropic is available on API Many from $4.40 per million input tokens and $22.00 per million output tokens, and you call it with the same API key you use for every other model.
It accepts OpenAI-style chat requests with streaming and tools, has a 128K context window and can return up to 16,000 tokens per response.
Claude models also speak the Anthropic Messages API at /v1/messages, so the official Anthropic SDK works by changing only the base URL.
Prompt caching is supported: cached input tokens are billed at the lower cached rate shown in the price table.
You pay only for successful results: failed or rejected requests are refunded automatically, and every call is recorded in your console with its exact cost.