Claude Sonnet 4
Practical Sonnet for assistants and high-volume work, announced May 2025.
Claude Sonnet 4 is the May 22, 2025 entry on the official Sonnet timeline. Anthropic frames it as an improvement over Sonnet 3.7, especially in coding, and as a practical frontier model for user-facing assistants and high-volume tasks. It remains in this catalog because the product page still lists it; it is not the default I would open today.
For current daily work, start with Claude Sonnet 5. For computer use as it exists now, see browser and computer use.