Claude Sonnet 5

Claude Sonnet 5 is Anthropic's most agentic Sonnet-class model, released June 30, 2026 as an upgrade to Sonnet 4.6 that narrows the gap to Opus 4.8 on reasoning, tool use, coding, computer use, and knowledge work while staying priced below the flagship. It launched at $2 per million input tokens and $10 per million output as introductory pricing through August 31, 2026, but Anthropic cancelled the scheduled September 1 increase to $3 and $15, so $2 and $10 is now the standard rate, with cache hits at $0.20. It ships a 1 million token context window with context compaction and adaptive thinking with selectable effort levels up to xhigh. Anthropic's own numbers show 85.2 on SWE-bench Verified, 63.2 on SWE-bench Pro, 78.3 on SWE-bench Multilingual, 81.2 on OSWorld-Verified, 84.7 on BrowseComp, and 80.4 on Terminal-Bench 2.1 (beating Opus 4.8 at 74.6 on that specific benchmark). Available on the Claude API, Amazon Bedrock, Google Vertex, and Microsoft Foundry at launch.