Anthropic launches Claude Opus 5.5 with lower costs and stronger safeguards

Anthropic has introduced Claude Opus 5.5, the first model in its Claude 5.5 family and the company’s new flagship for coding, computer use and knowledge work. Anthropic says the model performs around the level of Claude Fable 5.1 on most work while costing 40% less to run than Claude Opus 5 on typical workloads.

The practical change is price and throughput, not just benchmark movement. Anthropic lists Opus 5.5 at 4 USD per million input tokens and 20 USD per million output tokens, with cache reads at 0.20 USD per million tokens. The company says output generation is more than 30% faster than Opus 5, and that fast mode can reach up to 2.5x speed in Claude Code and the Claude Platform at higher token prices.

Anthropic is also presenting the release as a test of its “pace the frontier” stance. The company says Opus 5.5 was reviewed by external evaluators including Frontier Design and METR, scored best among its models on its automated behavioral audit, and is more resistant than Opus 5 to prompt injection.

Because Anthropic says Opus 5.5 is comparable to Claude Mythos 5.1 in biology and cybersecurity, access for some sensitive work will use verification programs. Vetted organizations can apply for life-science use, and expanded cyber verification is planned for verified practitioners.