Introducing Claude Sonnet 5.5
Claude @claudeai · x · 2026-09-28 · ★★★ · archived
Launch post for the second model of the Claude 5.5 family.
Summary
The Claude account introduced Sonnet 5.5 as a clear upgrade over Sonnet 5: over 30% faster and up to 30% cheaper per task at the same price, because it uses fewer tokens. It is strongest at well-scoped everyday tasks, bug fixing and documents/slides/spreadsheets. Haiku 5.5 is due in the coming weeks. @AnthropicAI: 'Claude Sonnet 5.5 is now available' (x.com/AnthropicAI/status/2104633259925630995). Verified via syndication: 2026-09-28T18:03:31Z.
Archived text
Introducing Claude Sonnet 5.5, the second model in the Claude 5.5 family.
It’s a clear upgrade over Sonnet 5, runs more than 30% faster, and costs up to 30% less for most work. https://t.co/UvXD8mDTF1
Media: https://pbs.twimg.com/media/HTUthyeWIAAInna.jpg
likes 51757 · replies 1654 (at fetch time)
Archived 2026-09-29 via syndication.
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