What is Claude Opus?

Claude Opus is Anthropic’s highest-capability large language model, positioned as a premium option for tasks requiring top-tier quality or security. It is also referenced as a benchmark for model size and capability in the industry.

• Jun 2026 - Nathan Labenz said that for security-critical tasks, people will pay up for the very best model like Opus.
• Jun 2026 - Ahmad Awais said that many people build one project with a high quality LLM like Opus to create a ‘taste file’, then use cheaper models to build on that.
• Jun 2026 - Greg Isenberg said that Fable low is better than Opus high.
• Jun 2026 - Nathaniel Whittemore said that a new Cursor model teased at Compile is the same size as Claude Opus and GPT-5, trained from scratch, with 10 to 20x more compute versus composer, and is generally intelligent, not just for coding, releasing in the next couple of weeks.