Anthropic’s official release of Claude Sonnet 4.5 represents a notable leap forward in AI technology specifically tailored for coding applications. This new frontier model is billed as achieving state-of-the-art performance on several standard coding benchmarks, while allowing developers to quickly create “production-ready” applications. The launch comes just two months after launching Claude Opus 4.1. This is a good example of Anthropic’s remarkable rapidity in pushing the state-of-the-art with AI technology.
Communicating its potential further, Claude Sonnet 4.5 exhibits exceptional performance on widely adopted coding benchmarks, including SWE-Bench Verified. This model greatly enhances the user experience. It empowers developers with an incredible tool that can code autonomously for up to 30 hours in early trials. As Anthropic touts, this model serves as their most aligned frontier AI yet. It is a striking improvement over earlier versions, producing lower rates of sycophancy and deception.
Claude Sonnet 4.5 is currently accessible via the Claude API as well as the Claude chatbot. This simplicity of use dynamic enables developers to instantly tap into its benefits. We price these at $3/million input tokens and $15/million output tokens. This affordability rate gives us a competitive edge in re-entering the post-COVID-19 market. This usage-based pricing structure ensures that smaller developers will be able to use the model without the burden of excessive costs.
Anthropic released the Claude Agent SDK in tandem with Claude Sonnet 4.5. This supplementary development greatly broadens their toolbox offering to web developers. This SDK makes it easy to add AI capabilities to any application, new or existing. It makes core improvements to the overall functionality and usability of the coding model.
To accompany this release, Anthropic is providing a limited research preview called “Imagine with Claude” that is available to Max subscribers. This Claude Sonnet 4.5 Preview Walkthrough allows you to get hands-on with some of these fantastic new capabilities. They can test these aspects out before a full rollout.
As Windsurf CEO Jeff Wang describes it, Claude Sonnet 4.5 represents a “new generation of coding models.” He emphasizes its ability to completely upend how we approach our coding-related tasks at work and home. By reducing susceptibility to prompt injection attacks, this model makes for a safer, more trusted coding experience.
Anthropic’s dedication to improving the state of AI technology is clearly on display in this new launch. Claude Sonnet 4.5 operates on the same infrastructure as Claude Code. This advanced design provides maximum performance and reliability in a variety of applications. The need for advanced, easy-to-use AI tools beyond chatbots is increasing. Claude Sonnet 4.5 is a great choice for developers who want best-in-class coding help.