Anthropic released Claude Opus 5.5 with 1M token context window, priced at $4 per million input tokens and $20 per million output tokens, achieving 40% cost reduction and 30% speed improvement over Opus 5, scoring 66.4% on Terminal-Bench 4.0 as a cost-effective alternative to Gable 5.1.
Claude Opus 5.5 (Max) achieved the top ranking in Code Arena: WebDev with 1818 points, leading GPT-6 Astra by 26 points and improving 126 points over the previous Opus 5 model.