PDFsam

PDFsam (short for PDF Split and Merge) is a powerful open-source desktop application built for users who need advanced control over PDF documents without relying on cloud-based tools. Available for Windows, macOS, and Linux, PDFsam lets you split, merge, rotate, mix, extract, and reorder pages with precision—all offline and completely free.

Unlike many online converters, PDFsam does not require internet access or file uploading, making it a great choice for sensitive document handling. It supports batch processing, customizable workflows, and full PDF/A compatibility. For users who need more, PDFsam also offers a paid version called PDFsam Enhanced, which adds OCR, PDF editing, form filling, and eSigning features.

With its open-source core and strong community support, PDFsam is an excellent pick for professionals, IT departments, and privacy-conscious users who want reliable desktop-based PDF processing.