If you prefer a standalone program over web-based tools, these options provide offline reliability and batch processing:

Unlike raw PSDs, PDFs allow you to set password protection and prevent unauthorized editing of your designs.

PSD to PDF: Maintaining Quality and Format During Conversion

For Windows users, Paint.NET is a free, lightweight tool. Once you install the community-made PSD plugin, it becomes a simple, one-click converter for your design files. Why Convert PSD to PDF?

PDFs preserve CMYK color profiles and high-resolution DPI settings, ensuring what you see on screen matches the final print.

A lightweight utility specifically designed for batch conversion. You can download this from sites like CNET to convert entire folders of PSDs into single or multiple PDF documents without needing Adobe Acrobat installed.