What is the best PDF file compressor for Windows 11?

PDFsam Basic is an open-source program that allows you to optimize and reduce the size of documents offline. As a fully localized pdf compressor, it does not require you to upload any files to the internet.

Instructions: Open the program, click Export/Save as Optimized Version, import the target PDF file, adjust the available compression settings, and finally start batch processing to save the compressed documents to your computer.

Its advantages include: offline local processing, with data stored on the device’s memory; automatic flattening of multi-layer PDFs and compression of embedded fonts to reduce file size; and support for batch document optimization.

Its disadvantages include: no adjustable custom DPI slider for fine-tuning images; a lack of a sophisticated, modern UI design; and the absence of advanced visual preview features before running compression tasks.

This allows you to safely optimize documents locally and serves as a reliable offline pdf compressor. It is suitable for routine batch compression of text-heavy and vector PDFs on your system, as well as for quickly reducing the size of layered local files without uploading data to cloud servers.