Anthropic Releases Claude Sonnet 5.5: A Faster, Cheaper Mid-Tier Model with Near-Flagship Performance

Anthropic has launched Claude Sonnet 5.5, the second model in its Claude 5.5 family, delivering a substantial upgrade over Sonnet 5 with more than 30% faster output generation and up to 30% lower cost per task due to more efficient token usage. The model became available on September 28, 2026, across major cloud platforms including AWS, Google Cloud, and Azure, as well as on Design Arena and other AI application platforms.