Claude Sonnet is an AI model created by Anthropic. The latest version, Claude Sonnet 4.6, is designed to be a practical, everyday AI workhorse, handling most tasks quickly and affordably. Anthropic positions Sonnet 4.6 as a balance between performance and cost-effectiveness, making it suitable for a wide range of users.
Sonnet 4.6 delivers coding capabilities close to Anthropic's most powerful model, Opus 4.6, at a lower cost. Recent benchmarks show Sonnet 4.6 achieving roughly 97-99% of Opus 4.6's coding ability. It excels in office tasks and demonstrates improvements in consistency, instruction following, computer use skills, long-context reasoning, agent planning, knowledge work, and design. Sonnet 4.6 also includes a 1 million-token context window (in beta), allowing for more complex and extended work sessions. As of February 2026, Sonnet 4.6 is the default model for free and Pro tier users across Claude interfaces. For API use, Sonnet 4.6 is priced at $3 per million input tokens and $15 per million output tokens.