Anthropic releases Claude Opus 4.5
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.
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.
Changelog
- 2026-09-29: created
Related events
- Anthropic releases Claude Sonnet 4.5 ★★★★
- Anthropic releases Claude Opus 4 and Sonnet 4; Claude Code goes GA ★★★★★
Sources (3)
- officialIntroducing Claude Opus 4.5 (Anthropic)
- officialClaude Opus (Anthropic product page)
- discussionWikipedia: Claude (language model)
id: 2025-11-24-claude-opus-4-5 · updated 2026-09-29 · open in the interactive timeline