Claude Opus 5 5

An Opus model for demanding reasoning, agentic coding, and large-codebase work. Compared with Opus 4.5, it emphasizes longer-horizon planning, code review, debugging, autonomous execution, and document and spreadsheet work, with a 1M-token context window and adaptive thinking. Evaluate newer Opus 4.7 or 4.8 first for new projects.

The Claude lineup workhorse, balancing strong intelligence, response speed, and cost. It supports a 1M-token context window and adaptive thinking, making it a strong starting point for coding, document analysis, data work, and tool-using agents; move to Opus for the most complex tasks.

An earlier Opus model in the Claude 4 family, focused on difficult coding, agents, computer use, deep research, and work with slides and spreadsheets. It fits workflows that require Opus-level capability with 4.5 compatibility; without that constraint, evaluate the newer Opus 4.6 or 4.7 first.

A flagship long-context model for demanding, long-running knowledge work, coding projects, and multi-step agentic tasks. It accepts text, images, and PDFs, making it a strong fit for cross-file analysis, complex research, and sustained tool use. It prioritizes reasoning depth and long-horizon execution over speed and cost, so it is best reserved for tasks where reliable completion matters.