AI model · by Anthropic
Claude Sonnet 5.5
Claude Sonnet 5.5 is Anthropic's quicker, cheaper model for routine, clearly defined work in coding, agents, and knowledge work.
- Released 28 Sept 2026
- 1M tokens context
- Closed weights
- Checked against Anthropic's page 19 Oct 2026
What Claude Sonnet 5.5 is for
Anthropic presents Sonnet 5.5 as a speedier, more economical counterpart to Opus 5.5, designed for straightforward daily tasks in coding, agents, and knowledge work. It suits agent jobs that demand dependable execution, including investigation, review, and drafting. Anyone can converse with it through Claude.ai on the web, iOS, and Android, while developers can construct agents with it via the Claude Platform or through AWS, Google Cloud, and Microsoft Foundry.
What Anthropic says it does well
- Well-defined agent tasks that need reliable execution, such as investigation, review, and drafting
Where to use it
- Claude.ai, available on web, iOS, and Android, for anyone to chat with Claude
- Claude Platform natively, and Amazon Web Services, Google Cloud, and Microsoft Foundry, for developers building agents