Claude by Anthropic
Claude is an AI assistant made by Anthropic, an AI safety company. Current models include Claude Opus 5, Sonnet 5, and Haiku 4.5, plus the higher-tier Mythos and Fable 5.1. Claude is accessible via claude.ai, mobile/desktop apps, the API, Claude Code, Claude Cowork, and browser/Office extensions. Anthropic focuses on building safe, helpful, and honest AI systems.