Claude Opus 5
Anthropic's flagship for complex agentic coding and enterprise work, approaching Fable 5 on most benchmarks at half the cost per token
Claude Opus 5
Anthropic • July 2026
Training Data
Up to May 2026
Claude Opus 5
July 2026
Parameters
Not disclosed
Training Method
Advanced Constitutional AI with adaptive thinking on by default and effort-steered test-time compute
Context Window
1,000,000 tokens
Knowledge Cutoff
May 2026
Key Features
Fast Mode (2.5x faster) • Mid-conversation Tool Changes • 1M Context / 128K Output
Capabilities
Reasoning: Outstanding
Coding: Outstanding
Agentic Work: Outstanding
What's New in This Version
Step-change over Opus 4.8 in deep reasoning and long-horizon agentic work: more than doubles its Frontier-Bench score at lower cost per task, triples the next-best model on ARC-AGI 3, and beats Fable 5 on OSWorld 2.0 at roughly a third of the cost
Anthropic's flagship for complex agentic coding and enterprise work, approaching Fable 5 on most benchmarks at half the cost per token
What's New in This Version
Step-change over Opus 4.8 in deep reasoning and long-horizon agentic work: more than doubles its Frontier-Bench score at lower cost per task, triples the next-best model on ARC-AGI 3, and beats Fable 5 on OSWorld 2.0 at roughly a third of the cost
Technical Specifications
Key Features
Capabilities
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