There are a lot of things you can do to save space on your Mac computer.

Reducing the file size of PDF documents is one way to make them smaller. Less space is taken up by this.

The quality of the original PDF may be decreased if you do that.

If you need a high-quality PDF for a presentation or work assignment, you can save it to a cloud-based backup system or an external hard drive.

In order to reduce the file size of a PDF on your Mac, here's what you have to do.

How to reduce PDF file size on a Mac computer with Preview

This is the first thing. If Preview isn't your default app, click the PDF to open it.

A screenshot highlighting how to open a PDF using Preview, if it isn’t your default option.
Choose the Preview app.
Devon Delfino/Insider

There are two Go to the top of the page.

There are three. Go to the menu and select the file you want to export.

A screenshot highlighting how to export a PDF from Preview on Mac.
Choose Export.
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There are four. You can see a pop-up window over the top middle section of the PDF by clicking the drop-down menu.

A screenshot highlighting the option to reduce a PDF’s file size during exporting on a Mac.
Choose Reduce File Size.
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You can click save.

The file size of your new PDF can be checked by right-clicking the file and choosing Get info.

How to reduce PDF file size on a Mac computer using  compression software

You can use third-party compression software if you don't want to use Preview.

You may have to pay to download them. It depends on the software you use.

Third-party file compression can be used.

  • PDF Expert
  • Adobe Acrobat
  • PDF Compressor