According to Anthropic, Opus 5.5 performs at a level comparable to Claude Fable 5.1 on most work while costing 40% less to run than Opus 5. The company also said the model generates output more than 30% faster than its predecessor.
The new model is designed for complex tasks including coding, computer use, research and business workflows. Anthropic said early testers used Opus 5.5 for large-scale code migrations, software audits and other projects that previously required substantially more time and computing resources.
Opus 5.5 costs $4 per million input tokens and $20 per million output tokens, compared with $5 and $25, respectively, for Opus 5. Cache reads cost $0.20 per million tokens, down from $0.50.
Anthropic said Opus 5.5 also achieved its strongest results to date on the company’s automated behavioral audit, which evaluates models across thousands of simulated scenarios. The company has introduced additional safeguards for cybersecurity, biology and protection against model distillation.
Claude Opus 5.5 is available today. [https://t.co/lSCmTYw9eJ](https://t.co/lSCmTYw9eJ)
[September 22, 2026](https://x.com/AnthropicAI/status/2102435703535939725?ref_src=twsrc%5Etfw)
The AI model is now available across Anthropic’s platforms, as well as Amazon Web Services, Google Cloud and Microsoft Azure. Developers can access it through the Claude Platform under the model name claude-opus-5-5.
Anthropic said Claude Sonnet 5.5 and Claude Haiku 5.5 will follow in the coming weeks.
Earlier, Qazinform News Agency reported that Anthropic had launched Opus 5, its latest AI model at the time, which the company said approached the capabilities of its more powerful Fable 5 at half the price.