Anthropic confirms Claude Sonnet 5.5 and Haiku 5.5 launching in coming weeks
alexalbert__ · x · 2026-09-23
Anthropic's mikeyk officially announced Claude Sonnet 5.5 and Haiku 5.5 will launch in the coming weeks, bringing many of the same performance, efficiency, and safety improvements as Opus 5.5. Product lead alexalbert teased "lots more coming soon — today is just the start."
Related event: Anthropic Teases Sonnet 5.5 and Haiku 5.5 Within Weeks(2 posts)→
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