American artificial intelligence company Anthropic has announced the launch of Sonnet 4.6, the latest version of its mid-sized model Sonnet, continuing the company’s iteration rhythm of every four months. Officials stated that the new version has been significantly improved in terms of code writing, instruction following, and computer operation. Sonnet 4.6 will immediately become the default model for both free and paid Pro users.
The beta version of Sonnet 4.6 released this time will support a context window of up to 1 million tokens, which is twice the maximum context available in the previous Sonnet series. Anthropic describes this capacity as "enough to accommodate an entire code base, a lengthy contract, or dozens of research papers in a single request." Greater context means models are able to retain more key information in a conversation when dealing with complex engineering projects, legal texts and academic materials.
The launch of Sonnet 4.6 comes just two weeks after the launch of the high-end model Opus 4.6, and the industry expects that the smaller Haiku model will also receive an update in the coming weeks. This shows that Anthropic is maintaining a tight product upgrade rhythm around different size models to cover multiple usage scenarios from lightweight to flagship.
In terms of performance, Anthropic said Sonnet 4.6 broke multiple benchmark records, including OS World, which measures computer operation capabilities, and SWE-Bench, which measures software engineering capabilities. Even more impressively, Sonnet 4.6 achieved a score of 60.4% on the ARC-AGI-2 test, which assesses "human-like intelligence" capabilities. This score puts the Sonnet 4.6 above most models in its class, but still lags behind high-end models like the Opus 4.6, Gemini 3 Deep Think, and the fine-tuned GPT 5.2 in overall performance.
From a product strategy perspective, Anthropic is trying to consolidate its competitiveness in fields such as general AI office, software development and long text processing by continuing to strengthen the Sonnet series in the mid-range price range. With doubled context windows and enhanced reasoning capabilities, Sonnet 4.6 is expected to further appeal to enterprise and developer users who need to deal with large code repositories and complex business documents.