Anthropic has launched Claude Sonnet 4.5, its newest AI model, claiming significant advancements in autonomous work and coding.
The company said that the model was able to run autonomously for 30 hours, maintaining sustained focus with minimal oversight while building an entire software application. It’s a significant improvement over the company’s previous Opus 4 model, released four months ago, which could operate autonomously for only seven hours.
Anthropic said Claude Sonnet 4.5 also outperformed Opus on key benchmarks and was more effective in meeting customers’ practical business needs. The company said the model was even better at coding than previous frontier models, and state-of-the-art on SWE-Bench Verified, a key benchmark that tests how models perform at software development tasks. Anthropic said that Claude Sonnet 4.5 was better than its predecessors at following instructions, identifying code improvements, and generating more production-ready code. When tested on tasks from the financial services industry, the company said the new model outperformed earlier Claude models in tasks such as researching, building financial models, and forecasting.
Anthropic appears to be pushing further ahead of its competitors in coding assistance and autonomous task completion, positioning its models toward corporate and workplace use. The company’s previous Claude Opus 4.1 model already bested competitors on OpenAI’s new benchmark of professional task completion, GDPval, which tested how models performed compared with human professionals across a range of industries and jobs.
