DeepSeek

DeepSeek Chat provides an intuitive online workspace driven by the company's frontier open-source language models, including the advanced DeepSeek-V4 and reasoning-focused R1 architectures. The web interface allows users to switch between different processing workflows, including a highly accelerated context mode and a rigorous deep-thinking toggle engineered for complex logic, mathematical operations, and algorithmic development. Key features of the system include an optional real-time web search engine to gather up-to-date data, synchronized conversation histories, and an integrated drag-and-drop document upload channel that extracts and reads code blocks, images, spreadsheets, and multi-page PDFs. Completely free to the public, DeepSeek Chat delivers immense practical value to students, developers, and knowledge workers by automating complex software refactoring, text summarization, and multi-document analysis within a high-capacity, long-context window.