Claude Opus 5.5 launches: Fable 5.1-level performance at 40% less cost
EricBuess · x · 2026-09-23
Anthropic introduced Claude Opus 5.5, the first model in the 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.
Related event: Anthropic Launches Claude Opus 5.5: Smarter and 40% Cheaper(46 posts)→
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