Claude Opus 5.5 Debuts: 40% Cheaper, ~30% Faster Than Opus 5, Stronger Agentic Coding
nicolechirps · x · 2026-09-23
Anthropic officially launched Claude Opus 5.5, the first model in the Claude 5.5 family, claiming it matches Claude Fable 5.1 on most tasks while costing 40% less to run than Opus 5.
Shayne Redford's summary of the key improvements:
- 40% cheaper than Opus 5 and 30% faster
- Stronger at agentic coding and computer use than Astra (CursorBench, KWBench, OSWorld)
- Much better style and instruction following
- Significantly stronger science and health capabilities
- Markedly more robust against cyber/bio threats
Related event: Anthropic Launches Claude Opus 5.5: Smarter, Faster, 40% Cheaper(63 posts)→
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