Anthropic releases Claude Opus 4.5
Confirmed
Importance: major (4 of 5)The takeaway
Claude Opus 4.5 set a new state of the art on SWE-bench Verified (80.9%) at a much lower price than prior Opus models, and Anthropic reported it scored higher than any human candidate ever on its take-home performance-engineering exam.
Status
- Claim
Confirmed
- Our reporting
- High confidence
- Importance
- Major (4 of 5)
- Last verified
- 11 October 2026
Your AI and this story
- GPT-6 AstraIn its training data
- Claude Opus 5.5In its training data
- Gemini 4 HydrogenIn its training data
- Grok 4.7In its training data
It happened before the cutoffs of all four assistants, so it can be in their training data.
Key facts
- Released 24 November 2025
- SWE-bench Verified: 80.9% (first model above 80%), per Anthropic’s published results
- Scored higher than any human candidate ever on Anthropic’s 2-hour performance-engineering take-home exam
- Price: $5 / $25 per million input/output tokens (down from $15 / $75)
- New ‘effort’ parameter to trade off speed and thoroughness
What happened
Anthropic released its most capable model of 2025, emphasizing coding, agents and computer use.
Why it matters
Made frontier-level agentic coding cheaper and helped drive rapid adoption of long-running coding agents at the end of 2025.
Sources
5 sources from 2 sites. Numbers match the chips in the text.
5 sources: 4 primary, 1 reaction
Primary
- Anthropic Engineering: Introducing advanced tool use on the Claude Developer Platform (Nov 24, 2025)anthropic.com, official
- Anthropic Engineering: Effective harnesses for long-running agents (Nov 26, 2025)anthropic.com, official
- Introducing Claude Opus 4.5 (Anthropic)anthropic.com, official
- Claude Opus (Anthropic product page)anthropic.com, official
Reactions
- Wikipedia: Claude (language model)en.wikipedia.org, discussion
Changes
- Added related Anthropic engineering post link(s)
- Filed