Anthropic Claude 3.7 Sonnet LLM

Superseded and retired

Claude 3.7 Sonnet (claude-3-7-sonnet-20250219) was deprecated on 2025-10-28 and retired on the Claude API on 2026-02-19, with claude-sonnet-4-6 as the recommended replacement (Anthropic model deprecations page, accessed 2026-10-02). The Sonnet line has since moved on: see claude-sonnet-5 and anthropic-claude for the current lineup. Partner platforms (Bedrock, Vertex AI) set their own retirement dates.

Claude 3.7 Sonnet

Claude 3.7 Sonnet was released by anthropic on 2025-02-24 as the successor to Claude 3.5 Sonnet. Anthropic called it the first hybrid reasoning model: one model that can answer instantly or use extended thinking, with an API-settable thinking-token budget. Thinking tokens were billed as output tokens (Anthropic launch post).

Claude Sonnet models were popular for writing and coding, particularly tool calling. Claude 3.5 Haiku was the smaller, cheaper sibling (also retired 2026-02-19).

Sources

• https://www.anthropic.com/news/claude-3-7-sonnet (accessed 2026-10-02)
• https://platform.claude.com/docs/en/about-claude/model-deprecations (accessed 2026-10-02)