Anthropic launches Sonnet 5.5: 30% faster and up to 30% cheaper than Sonnet 5
felixrieseberg · x · 2026-09-29
Felix Rieseberg announces the launch of Claude Sonnet 5.5: smarter and more tasteful than Sonnet 5, positioned for workloads that don't need the power of Opus or Fable.
Key numbers: 30% faster and up to 30% cheaper for most work. He also had it build a few games, shared in the thread as demos.
Related event: Anthropic Launches Claude Sonnet 5.5: 30% Faster, 30% Cheaper(31 posts)→
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