Anthropic has upgraded Claude Sonnet 4 with a 1M token context window, competing with OpenAI's GPT-5 and Meta's Llama 4.

The company today revealed that Claude Sonnet 4 now supports up to 1 million tokens of context in the Anthropic API — a five-fold increase over the previous limit.

Claude Sonnet 4 can now support up to one million tokens of context, marking a fivefold increase from the prior 200,000, ...

Anthropic’s developers recently upgraded the AI model Claude Sonnet 4 to support up to 1 million tokens of context, thereby ...

To account for the extra computing power required for large requests, Anthropic will increase the cost for Claude Sonnet 4 ...

Anthropic has expanded the capabilities of its Claude Sonnet 4 AI model to handle up to one million tokens of context, five ...

Anthropic upgrades Claude Sonnet 4 to a 1M token context window and adds memory, enabling full codebase analysis, long ...

Dan Shipper in Vibe Check Was this newsletter forwarded to you? Sign up to get it in your inbox. Today, Anthropic is releasing a version of Claude Sonnet 4 that has a 1-million token context window.

According to Anthropic, Claude Sonnet 4 is a significant upgrade to Claude Sonnet 3.7, offering improved coding and reasoning along with the ability to respond to instructions more precisely.

Claude Opus 4 excels at coding and complex problem-solving, whereas Claude Sonnet 4 improves on Sonnet 3.7 and balances performance and efficiency.

Anthropic says Claude Opus 4 and Sonnet 4 outperform rivals like OpenAI's o3 and Gemini 2.5 Pro on key benchmarks for agentic coding tasks like SWE-bench and Terminal-bench.

Free users of Claude can only access the new Sonnet 4 model. However, Pro, Max, Team, and Enterprise Claude plan users can access both models and extended thinking.