Claude 3.5 Sonnet

Claude 3.5 Sonnet is a text-and-image language model from Anthropic, first released in June 2024 as a mid-tier upgrade to the Claude 3 lineup that matched or beat the larger Claude 3 Opus on most benchmarks while running faster and cheaper. Anthropic updated it again in October 2024 with a version that added computer use, a feature letting the model view a screenshot and control a mouse and keyboard to operate software the way a person would. That update made Claude 3.5 Sonnet one of the first widely available models built for agentic tasks like filling out web forms, navigating operating systems, and running multi-step workflows without a human clicking each button. It kept the 200,000 token context window of its predecessors and priced at $3 per million input tokens and $15 per million output tokens, positioning it as Anthropic’s workhorse model through much of 2024 and early 2025 before the Claude 3.7 and Claude 4 lines replaced it.