Claude Opus 4 is an AI model released by Anthropic on May 22 2025, 0 days after Claude Sonnet 4. It is the 12th tracked release from Anthropic out of 19 total.
On published benchmarks, it scores 79.6% on GPQA Diamond (graduate-level science reasoning), 72.5% on SWE-Bench Verified (real-world software engineering).
About Anthropic: AI safety company building the Claude family of models. Founded in 2021 by former OpenAI researchers.