sift-kg is a command-line tool that converts unstructured document collections into knowledge graphs using large language models (LLMs) to extract entities and relationships. The tool deduplicates extracted information with user approval and generates an interactive graph viewer in a web browser. This process takes minutes, compared to months spent building knowledge bases in tools like Notion or Obsidian. The tool supports 75+ document formats and can export the generated graph to various formats, including graph databases and visualization software. This technology matters to AI developers and operators as it provides a rapid and structured understanding of complex information, enabling improved data analysis and visualization.