Key Info

Anthropic released Claude Sonnet 5.5, the second model in the Claude 5.5 family, claiming a clear upgrade over Sonnet 5 with over 30% faster performance and up to 30% lower cost for most workloads.

Highlights

  • Faster than Sonnet 5 by more than 30% while costing up to 30% less for most tasks
  • Improves on or matches Sonnet 5 across most automated behavioral audit measures of alignment and honesty
  • First Sonnet model to include cyber safeguards and fallbacks like those on Anthropic's most capable models, with routine software development unaffected
  • Available everywhere today; Claude Haiku 5.5 will join the family in coming weeks