Sonnet 5.5

Anthropic has released Claude Sonnet 5.5, the second model in its Claude 5.5 family following last week's Opus 5.5. The model runs more than 30% faster and costs up to 30% less for most work while keeping Sonnet 5's per-token pricing.

Anthropic has released Sonnet 5.5, the latest version of its mid-tier Claude model, claiming 30% faster performance and significantly lower token costs than its predecessor. The company says the model now outperforms Opus 5.5 on agentic coding tasks and carries cyber capabilities comparable to Opus 5.