Claude Haiku 4.5 is an AI model released by Anthropic on Oct 15 2025, 16 days after Claude Sonnet 4.5. It is the 15th tracked release from Anthropic out of 19 total.
On published benchmarks, it scores 73% on GPQA Diamond (graduate-level science reasoning), 73.3% 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.