Claude 3.7 Sonnet and Claude Code

Today, we’re announcing Claude 3.7 Sonnet 1 , our most intelligent model to date and the first hybrid reasoning model on the market. Claude 3.7 Sonnet can produce near-instant responses or extended, step-by-step thinking that is made visible to the user . API users also have fine-grained control over how long the model can think for.

Claude 3.7 Sonnet shows particularly strong improvements in coding and front-end web development. Along with the model, we’re also introducing a command line tool for agentic coding, Claude Code. Claude Code is available as a limited research preview, and enables developers to delegate substantial engineering tasks to Claude directly from their terminal.

Claude 3.7 Sonnet is now available on all Claude plans—including Free, Pro, Team, and Enterprise—as well as the Claude Developer Platform , Amazon Bedrock , and Google Cloud’s Vertex AI . Extended thinking mode is available on all surfaces except the free Claude tier.

Third, in developing our reasoning models, we’ve optimized somewhat less for math and computer science competition problems, and instead shifted focus towards real-world tasks that better reflect how businesses actually use LLMs.

Early testing demonstrated Claude’s leadership in coding capabilities across the board: Cursor noted Claude is once again best-in-class for real-world coding tasks, with significant improvements in areas ranging from handling complex codebases to advanced tool use. Cognition found it far better than any other model at planning code changes and handling full-stack updates. Vercel highlighted Claude’s exceptional precision for complex agent workflows, while Replit has successfully deployed Claude to build sophisticated web apps and dashboards from scratch, where other models stall. In Canva’s evaluations, Claude consistently produced production-ready code with superior design taste and drastically reduced errors.

In the coming weeks, we plan to continually improve it based on our usage: enhancing tool call reliability, adding support for long-running commands, improved in-app rendering, and expanding Claude's own understanding of its capabilities.

In both standard and extended thinking modes, Claude 3.7 Sonnet has the same price as its predecessors: $3 per million input tokens and $15 per million output tokens—which includes thinking tokens.

We’ve developed Claude 3.7 Sonnet with a different philosophy from other reasoning models on the market. Just as humans use a single brain for both quick responses and deep reflection, we believe reasoning should be an integrated capability of frontier models rather than a separate model entirely. This unified approach also creates a more seamless experience for users.

Claude 3.7 Sonnet embodies this philosophy in several ways. First, Claude 3.7 Sonnet is both an ordinary LLM and a reasoning model in one: you can pick when you want the model to answer normally and when you want it to think longer before answering . In the standard mode, Claude 3.7 Sonnet represents an upgraded version of Claude 3.5 Sonnet. In extended thinking mode , it self-reflects before answering, which improves its performance on math, physics, instruction-following, coding, and many other tasks. We generally find that prompting for the model works similarly in both modes.