Anthropic unveils Claude Opus 5.5

Sept. 22 (Reuters) - Anthropic on Tuesday released Claude Opus 5.5, which it called its most powerful AI model to date, offering performance it said rivals its top-tier system at a significantly lower price.

The company said Opus 5.5 performs on par with its Claude Fable 5.1 model on most tasks while costing 40% less to run on typical workloads than its predecessor, Claude Opus 5.

The model is faster, cheaper and writes more clearly than earlier versions, Anthropic said, while outperforming its recent models on internal safety tests, and being 85% less likely than Opus 5 or Mythos 5.1 to attempt to bypass its prescribed boundaries.

The model is priced at $4 per million input tokens and $20 per million output tokens, 20% below Opus 5.