Anthropic boosts Claude Sonnet 4 AI memory to handle bigger coding projects with new update

Claude AI

Anthropic has increased the context window for its Claude Sonnet 4 model to 1 million tokens, a fivefold expansion from its previous 200,000-token limit. The move is aimed at strengthening its position in the competitive AI coding market, where it faces rivals such as OpenAI and Google.

Context windows define the amount of information an AI model can process at once. According to Anthropic, the new limit enables Claude Sonnet 4 to handle the equivalent of 2,500 pages of text or an entire copy of War and Peace in a single request. In coding tasks, the capacity has increased from around 20,000 lines of code to between 75,000 and 110,000 lines, allowing for complete code base analysis without splitting projects into smaller segments.

Brad Abrams, product lead for Claude, told The Verge that the larger context window addresses one of the most frequent challenges for enterprise customers, the need to break problems into smaller parts. Anthropic said the change will benefit clients across sectors including software development, pharmaceuticals, retail, professional services, and legal services.

While significant, the expansion matches a capability OpenAI introduced in April with its GPT-4.1 model. The announcement follows OpenAI’s recent launch of GPT-5, which highlighted improved coding benchmarks. Anthropic has historically been recognised for strong coding performance and appears to be positioning this update as a step to maintain competitiveness.

The update comes as Anthropic is reportedly in talks to raise funding at a valuation of up to $170 billion. Enterprise customers, who are willing to pay premium rates for advanced coding and document analysis capabilities, represent a key revenue stream for both Anthropic and OpenAI.

The 1 million-token context window is initially available through Anthropic’s API to Tier 4 and custom-rate-limit customers, with broader access planned in the coming weeks, according to the company’s blog post.