On May 22, 2025, Anthropic released Claude Opus 4 alongside Claude Sonnet 4. Anthropic classified Opus 4 as a "Level 3" model on its four-point safety scale, meaning it poses "significantly higher risk" due to its capabilities.
The company continued rapid iteration, releasing Opus 4.1 in August, Opus 4.5 in November (best-in-class for coding and agents), and Opus 4.6 on February 5, 2026 with a 1M context window.