Claude

Claude is made by Anthropic and named after Claude Shannon, the founder of information theory. Since the Claude 3 generation (2024), each generation comes in tiers, with Haiku as the small, fast model, Sonnet as the balanced model and Opus as the largest; newer lines can be added. Claude is used for chat, writing, coding and agents, including Anthropic's own coding agent, Claude Code.

Claude models are transformers post-trained with Anthropic's Constitutional AI method (published in 2022), in which the model critiques and revises its own outputs against a written set of principles, alongside reinforcement learning from feedback. Claude models support tool use and extended thinking, where the model reasons before answering and the thinking tokens are billed as output. Anthropic sells Claude through its own API and through cloud platforms such as Amazon Bedrock and Google Cloud Vertex AI.

Anthropic does not disclose model sizes or training compute. Context window, prices and thinking budgets differ by model and change between generations; the live block lists them per model. Because the same model is served by several clouds, BenchGecko tracks each provider offer separately.