Claude Opus 5.5 Debuts at Fable 5.1-Level Performance With 40% Lower Running Costs

a_baaron · x · 2026-09-23

Anthropic released Claude Opus 5.5, the first model in its new Claude 5.5 family. It performs at the level of Claude Fable 5.1 for most tasks and costs 40% less to run than Opus 5. Early users praise its everyday usability and plain-English writing.

Related event: Anthropic Launches Claude Opus 5.5: Smarter, Faster, 40% Cheaper(65 posts)→

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