Anthropic has released Claude Opus 5.5, the first model in its new Claude 5.5 family, which performs at the level of Claude Fable 5.1 on most work while costing 40% less to run than Opus 5.
- Opus 5.5 leads in agentic coding, computer use, and knowledge work benchmarks, including Terminal-Bench 4.0 (66.4%) and FrontierCode v1.1 (54.4%).
- Pricing drops to $4 per 1M input tokens and $20 per 1M output tokens, with cache reads reduced by 60% to $0.20.
- Output generation is more than 30% faster than Opus 5, and fast mode offers up to 2.5x speed at higher rates.
- The model ships with Fable 5.1-class safeguards for biology and cybersecurity, and thinking can no longer be disabled.
- It is available as a managed API on the Claude Platform, AWS, Google Cloud, and Microsoft Azure, but weights are not released.
The release provides developers with a high-performance option that significantly reduces running costs for typical workloads while maintaining strict safety standards.