Claude 4.5 Opus is Anthropic's most advanced AI model as of late 2025, designed for complex reasoning, coding, and agentic workflows. It excels in tasks requiring sustained reasoning, long-term context retention, and precise execution. Anthropic positions it as the best model for coding, agents, and computer use, outperforming previous models like Sonnet 4.5 and Opus 4.1. Key features include improved multilingual coding performance, efficient code generation, stronger test coverage, and enhanced capabilities in handling complex projects end-to-end. It also showcases improvements in safety and security with a reduced rate of misaligned responses and stronger robustness against prompt-injection attacks.
Claude Opus 4.5 is available through Anthropic's API, Amazon Bedrock, Microsoft Foundry, GitHub Copilot, and Microsoft Copilot Studio. As of November 2025, its pricing is set at $5 per million input tokens and $25 per million output tokens. It supports a context window of up to 200,000 tokens and can generate up to 64,000 tokens in a single output. The model has been trained on data up to May 2025. It is considered a hybrid reasoning model where users can toggle between a default mode for rapid responses and an "extended thinking" mode for more deliberation.
