Claude Sonnet 5.5 API

Claude Sonnet 5.5 is available through the zcloud gateway behind one API key, alongside every other model in the catalog. Claude Sonnet 5.5 API pricing is pay-as-you-go: $0.20 per 1M input tokens and $1.00 per 1M output tokens — no subscription, no monthly minimum, and the same OpenAI-compatible endpoint your tools already use.

Against the official API — $2.00 input and $10.00 output per 1M tokens — zcloud runs about 90% cheaper, so sustained workloads cost a fraction of list price. Every request is metered per token and settled in real time, and live rates stay visible on the pricing page. The model provides a 1,000,000 token context window, so long documents, large codebases and extended agent sessions fit in a single request.

For predictable spend, prepaid Token Plans for Claude Sonnet 5.5 start at $2 and are consumed first; PAYG covers anything beyond the plan. Claude Sonnet 5.5 runs behind the same OpenAI-compatible and Anthropic-compatible endpoints as the rest of the catalog, so existing tooling keeps working after a one-line base-URL change — a practical fit for chat products, coding agents and batch jobs that need frontier quality without official-API prices.