Claude 4.5 Opus
modelFirst model to exceed 80% on SWE-bench Verified. 200K token context. Also released as Claude 4.5 Sonnet (September 2025, 1M context, AA 37) and Claude 4.5 Haiku (October 2025, AA 31). Architecture undisclosed.
AA Intelligence Index: 43. Claude 4.5 Opus was the highest-ranked non-reasoning model at the time of release, with particular strength in coding, writing, and multi-step agentic tasks. Proprietary.
Model Details
Context window 200,000
Variants
| Name | Parameters | Notes |
|---|---|---|
| Claude 4.5 Sonnet | — | 1M context, AA index 37 |
| Claude 4.5 Haiku | — | 200K context, AA index 31 |
| Claude 4.5 Opus | — | 200K context, AA index 43 |