How to compress a pdf file on mac without losing quality

Automator is a great, built-in way to compress a PDF file on Mac. You're basically building a custom little tool that lives right in your Finder's right-click menu, so you can compress PDFs with just one click . It works by using Apple's built-in "Quartz Filters" to re-encode and shrink the images inside the PDF.

How to compress a PDF file on mac:

1. Open Automator and choose to create a new Quick Action. Set it to receive PDF files in the Finder .
2. Add the action: Search for "quartz" and drag the Apply Quartz Filter to PDF Documents action into your workflow .
3. Pick a filter: In the action, choose a filter from the dropdown menu. You can use the default Reduce File Size, or create a custom one for better quality control using the ColorSync Utility app .
4. Save it: Give your Quick Action a name, like "Compress PDF."

Once saved, you can right-click (or Control-click) any PDF in the Finder, go to Quick Actions, and choose your new tool. Automator will then apply the filter and compress a PDF file on Mac for you in seconds.

This is honestly one of the easiest ways how to compress a PDF file on Mac for free, and it uses only native macOS tools. The only catch is that the compression can be quite aggressive, so the image quality might drop noticeably. It's great for quick sharing or archiving, but if quality matters, you might want to test it first or explore other options. Still, for a free, built-in method, Automator is a hidden gem.