How to merge PDF files on a Mac (4 free ways)

Unlike Windows, macOS can merge PDFs out of the box — in fact in several ways. The catch is that the built-in methods are a little hidden and each has quirks: Preview’s drag-and-drop is fiddly, Finder decides the order for you, and it’s easy to overwrite the original. Here are the four methods that work, when to use each, and how to fix the usual problems.

Quick comparison

Method 1: Finder Quick Action (the fastest)

Since macOS Mojave, Finder can create a PDF from several files in one click:

1. Put the PDFs in the same folder. Rename them with a number prefix — 01-cover.pdf, 02-contract.pdf, 03-annex.pdf — so they sort in the order you want.
2. Sort the window by name and select the files (Cmd-click to pick several).
3. Control-click (or right-click) the selection and choose Quick Actions > Create PDF.

A new PDF appears in the folder, named after the first file. The same action also works with images: select JPGs or HEIC photos and you get a multi-page PDF.

Limits: you can’t reorder inside the action, and there are no options for page size. Check the result and fix the order in Preview if needed.

Method 2: Preview (precise, but fiddly)

Preview is the tool most guides mention. It’s powerful once you know the trick:

1. Make a copy first: open the first PDF and choose File > Duplicate, or plan to use Export at the end. Preview saves changes into the open file.
2. Choose View > Thumbnails to show page thumbnails in the sidebar.
3. Drag the second PDF from Finder into the sidebar, between two thumbnails or below the last one. A line shows where the pages will land. Alternatively, select a thumbnail and use Edit > Insert > Page from File.
4. Drag thumbnails to reorder pages; press Delete to remove a page.
5. Choose File > Export as PDF and give the merged file a new name.

Preview’s limitations:

• Dropping a file onto the main page instead of the sidebar opens it separately instead of merging.
• With many files, you have to drag them one by one and scroll a long thumbnail list.
• If you simply close the window, Preview keeps the changes in your original file.
• Password-protected PDFs must be unlocked before their pages can be inserted.

Method 3: Shortcuts (for merges you repeat)

If you merge the same kind of documents every month — invoices, timesheets — build a shortcut once:

1. Open the Shortcuts app and create a new shortcut.
2. In the shortcut’s details, enable Use as Quick Action and Finder, receiving PDFs.
3. Add the action Make PDF (it combines the input files), then Save File to choose where the result goes.

From now on, select files in Finder, Control-click and run your shortcut from Quick Actions. Shortcuts also exist on iPhone and iPad, so the same logic works there.

Method 4: a browser tool (clear ordering, any number of files)

When you have many files or want to see the order clearly, a web tool is simpler. Most online mergers upload your documents to their servers; Merge PDF on TurboConvert doesn’t — the merge runs inside Safari, Chrome or Firefox on your Mac.

1. Open Merge PDF and click Choose files, or drag the PDFs from Finder onto the page.
2. Use the arrows to put the files in the right order.
3. Click Convert. The merged PDF downloads to your Downloads folder.

Pages are copied as-is: text stays selectable, images aren’t recompressed, and mixed page sizes are kept. Bookmarks (the outline) from the original files are not carried over. Files up to 200 MB each are accepted.

Merging on iPhone and iPad

The Files app has the same feature as Finder:

1. Open Files and go to the folder that contains the PDFs (save attachments to Files first if needed).
2. Tap Select, then tap the PDFs in the order you want.
3. Tap the More button (three dots) and choose Create PDF.

The browser method works on iOS too: open Merge PDF in Safari and pick the files from the Files app.

Fixing common problems

The merged PDF is huge. Merging doesn’t add weight, but scans add up quickly. Run the result through Compress PDF once; see our guide on making a PDF small enough to email for the limits of Gmail, Outlook and iCloud.

One file refuses to merge. It’s probably encrypted. If you know the password, remove it with Unlock PDF (or open it in Preview, enter the password and export a copy), then merge.

Pages are sideways. Rotate them in Preview (select the thumbnail, press Cmd+R) or use Rotate PDF before merging.

You only need some pages of a file. Extract them first with Split PDF, or delete unwanted pages afterwards with Organize PDF.

Forms stop working after merging. Interactive form fields can conflict when two PDFs use the same field names. Fill and flatten the forms (in Preview: File > Print > Save as PDF) before merging.

You need page numbers across the merged document. Add them at the end with Add page numbers, so numbering follows the final order.

Before you send the merged file

A few checks save embarrassing back-and-forth:

• Scroll through every page at thumbnail size: a missing or duplicated page is obvious at a glance.
• Check the file size in Finder (Get Info). Over 20–25 MB, many email services will refuse it.
• Give it a clear name, such as Application-Martin-2026.pdf, rather than the name of the first file.
• Protect it if it’s sensitive: our guide to password-protecting a PDF shows how to do it in Preview.

Which method should you use?

• Two or three files, whole documents: Finder Quick Action.
• Insert a page in the middle of a document: Preview.
• The same merge every week: a Shortcut.
• Ten files or more, or you want to see and change the order easily: Merge PDF in your browser.

All four keep your files on your Mac — none of them uploads anything.