Claude Opus

Hybrid reasoning model built for serious coding and AI agents, featuring a 1M context window

NEW Claude Opus 5.5 Sep 22, 2026 We’re introducing Claude Opus 5.5. It performs at the level of Claude Fable 5.1 on most work and costs 40% less to run than Opus Read more - Claude Opus 5 Jul 24, 2026 A step-change impro

Claude Opus 5.5 is our strongest Opus model yet, powering long-running, highly capable agents while delivering improvements in coding and professional work. For business users and consumers who want to collaborate with a

Claude Opus 5.5 is our most capable Opus model yet for coding, agents, and knowledge work. It costs less per token than Opus 5 and uses fewer tokens per task, so work on the Claude Platform, in Claude Code, and in the Cl

Claude Opus 5.5 delivers the intelligence and reliability to be your daily driver for serious coding and knowledge work. Unless otherwise noted, all Claude Opus 5.5 results use adaptive thinking at max effort. Terminal-B

Extensive testing and evaluation ensures the release of Opus 5.5 meets Anthropic’s standards for safety, security, and reliability. The accompanying system card covers safety results in depth.

Opus 5.5 is the first Opus model to launch with a similar class of safeguards to Fable 5.1 in cybersecurity, biology, and anti-distillation. As our models grow more powerful, stricter safeguards are one way we prevent ne

Developers want agents that can take on real software work and finish it. In our testing across GitHub Copilot CLI and VS Code, Claude Opus 5.5 used among the fewest tokens and steps we measured. In VS Code, it solved mo