How to Merge PDF Files on a Mac (Preview and Free Online Methods)

The Short Answer

On a Mac you can merge PDFs in Preview by dragging page thumbnails from one file into another and saving. For several files at once, a browser tool such as Merge PDF is faster: add the files, drag them into order and download.

Method 1: Merge PDFs With Preview

Open the first PDF in Preview.
Show the thumbnails by choosing View, then Thumbnails.
Open the second PDF in its own window and show its thumbnails too.
Drag the pages you want from the second window into the thumbnail sidebar of the first, at the position you want them.
Check the order, then save with File, then Export as PDF.

Preview works well for two files. With five or ten documents it becomes slow, because you repeat the drag-and-drop for each one.

Method 2: Merge With a Browser Tool

Open Merge PDF in Safari or Chrome.
Select all your PDFs at once, up to 20 files.
Drag the file cards into the right order.
Click merge and download the combined PDF.

Nothing is uploaded. Your files are combined inside the browser on your Mac.

Which Method Should You Use?

Two files and you want to pick individual pages: Preview is fine.
Three or more files, or you want a visual order: the browser tool is quicker.
You are on a shared or work Mac and cannot install anything: use the browser tool.

Tips for a Clean Result

Delete unwanted pages first with Remove Pages.
Shrink the final file with Compress PDF if you plan to email it.
On iPhone or iPad, the browser tool works the same way in Safari. Read the full guide to merging PDFs on any device.