Claude Sonnet 4.5 was released September 29, 2025. Scored 77.2% on SWE-bench Verified (82.0% with parallel compute) and 61.4% on OSWorld. Maintained focus for 30+ hours on multi-step tasks. Launched alongside Claude Code 2.0. Priced at \$3/\$15 per million tokens with 200K context (1M beta).
Modality
text, image
Capabilities3
tool-useextended-thinkingagentic-coding
Details
Model FamilyClaude
Tiersonnet
Generation4.5
Release Date2025-09-29
Context Window200K tokens
Open WeightNo
Safety LevelASL-3
Tags
claudeclaude-4agentic-coding