Anthropic: Claude Opus 4.1

anthropic/claude-opus-4.1

Released Aug 5, 2025Knowledge cutoff Jan 31, 2025200,000 context$15/M input tokens$75/M output tokens

Claude Opus 4.1 is an updated version of Anthropic’s flagship model, offering improved performance in coding, reasoning, and agentic tasks. It achieves 74.5% on SWE-bench Verified and shows notable gains in multi-file code refactoring, debugging precision, and detail-oriented reasoning. The model supports extended thinking up to 64K tokens and is optimized for tasks involving research, data analysis, and tool-assisted reasoning.

Anthropic: Claude Opus 4.1

anthropic/claude-opus-4.1

Released Aug 5, 2025Knowledge cutoff Jan 31, 2025200,000 context$15/M input tokens$75/M output tokens

Claude Opus 4.1 is an updated version of Anthropic’s flagship model, offering improved performance in coding, reasoning, and agentic tasks. It achieves 74.5% on SWE-bench Verified and shows notable gains in multi-file code refactoring, debugging precision, and detail-oriented reasoning. The model supports extended thinking up to 64K tokens and is optimized for tasks involving research, data analysis, and tool-assisted reasoning.

Sample code and API for Claude Opus 4.1

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