Claude Opus 5.5
by Anthropic
Claude Opus 5.5 is Anthropic's flagship model for demanding reasoning, coding, and long-horizon agentic work, succeeding Claude Opus 5. It is particularly strong at multi-step chan
Models
Claude Opus 5.5
Added 24 Sept 2026
Overview
Claude Opus 5.5 is Anthropic's flagship model for demanding reasoning, coding, and long-horizon agentic work, succeeding Claude Opus 5. It is particularly strong at multi-step changes in large codebases, code...
How to use / API access
Call via OpenRouter with model id `anthropic/claude-opus-5.5`.
- openrouter ·
anthropic/claude-opus-5.5Docs
OpenRouter id: anthropic/claude-opus-5.5
Benchmarks
- Intelligence Index (artificial-analysis) : 57.6 index
- Design Arena mobileapps (other) : 1268 elo · #5
- Design Arena 3d (other) : 1450 elo · #1
- Design Arena gamedev (other) : 1485 elo · #1
- Design Arena svg (other) : 1325 elo · #2
Notes
Claude Opus 5.5 is listed in the EDNA Models directory from the OpenRouter catalogue.
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