Ledge

How to merge PDFs from different folders on a Mac

· 6 min read

Open the first PDF in Preview, choose View > Thumbnails, and drag the other PDFs from Finder into the sidebar. Their pages join the open document at the spot where you drop them. Preview is on every Mac, so there is nothing to install. The two things that trip people up are where exactly to drop, and the fact that Preview saves the change into the file you opened.

Protect the original first

Preview saves as you work. Once you add pages to a PDF, the file on disk becomes the merged version, and there is no Save button holding the change back. If the first PDF is one you need to keep as it is, make a copy before anything else.

  1. Open the first PDF in Preview.
  2. Choose File > Duplicate (Shift-Command-S).
  3. Give the copy a clear name, such as Application packet, and work in that window.

You can do the same in Finder by selecting the file and pressing Command-D. Either way, merge into the copy. If you forget and merge into the original, choose File > Revert To > Browse All Versions to step back to the earlier state.

Merge whole PDFs in Preview

  1. With the copy open, choose View > Thumbnails (Option-Command-2). A sidebar shows every page.
  2. Click the thumbnail the new pages should follow. To add to the end, select the last page.
  3. Choose Edit > Insert > Page from File, select the second PDF and click Open. All of its pages are inserted after the page you selected.
  4. Repeat for each further PDF.

Dragging does the same job with less clicking. Drag a PDF’s icon from a Finder window into the sidebar and watch for the line that shows where the pages will land, then let go. Drop onto the existing thumbnails, not into the empty area below them. If Preview shows the new file as a separate document in the sidebar instead of adding its pages to the list, press Command-Z and drop again, directly on top of a page thumbnail.

When you are done, close the window and the copy keeps everything. If you would rather write a fresh file under a new name, choose File > Export as PDF.

Take only some pages from another PDF

You do not have to bring in a whole document.

  1. Open both PDFs in Preview, each in its own window, with thumbnails showing in both.
  2. In the source window, click the page you want. Command-click to pick several, or Shift-click for a range.
  3. Drag the selected thumbnails into the other window’s sidebar and drop them where they belong.

The pages are copied, so the source PDF keeps all of its pages. If what you want is a single page as its own file, How to drag a single page out of a PDF on a Mac covers that direction.

Fix the order and remove pages

Merging rarely lands in the right order on the first try. The sidebar is where you fix it.

  • Reorder. Drag a thumbnail up or down. Select several first to move them as a group.
  • Delete. Select a page and press Delete.
  • Rotate. Select a sideways scan and press Command-R or Command-L to turn it.
  • See more at once. For a long document, choose View > Contact Sheet to lay the pages out in a grid and drag them around there.

The Finder shortcut for a simple merge

When you want whole documents joined and nothing else, you can skip Preview.

  1. In a Finder window, click the PDF that should come first.
  2. Command-click the others in the order they should follow. The pages are arranged in the order you select the files.
  3. Control-click one of the selected files and choose Quick Actions > Create PDF.

A new PDF appears in the same folder and the originals are left alone. The limits are that every file has to be in the same Finder window, and you cannot choose individual pages. If the order comes out wrong, open the result in Preview and drag the thumbnails. The same command works on pictures, which How to combine several images into one PDF on a Mac walks through.

When the PDFs live in different places

The awkward part of a real merge is usually not the merging. The bank statement is in Downloads, the signed form is attached to an email, a scan is on the desktop and the contract sits three levels down in a project folder. A Finder selection lives in one window, and Preview wants each file dragged in while its sidebar is visible, so you end up arranging and rearranging windows.

The plain route is to make a working folder, hold Option while you drag each PDF into it so you copy instead of move, and merge from there.

Ledge shortens the gathering. As you come across each PDF, drag it up to the notch at the top of the screen and let go. It lands on a shelf that drops from the notch and stays there until you take it somewhere, so you can collect from several apps and folders without keeping any window in position. When every piece is on the shelf, open the first PDF in Preview with thumbnails showing, press Option-Space or click the notch to open the shelf, and drag each PDF into the sidebar in the order you want. On a Mac without a notch, the shelf sits at the top center of the screen.

To be plain about the limits: Ledge does not merge, split or edit PDFs, and it does not read or index what is inside them. Preview does the merging. The shelf is a place for the files to wait while you find the rest. There is no account and no cloud, and files never leave the Mac, which matters when the documents are statements, IDs or signed forms. Ledge needs macOS 14 Sonoma or later and is free for 14 days, then $19 once.

Problems you may run into

  • A PDF asks for a password. Preview asks when you open it, and the file has to be unlocked before its pages can be combined with anything. If you do not have the password, ask whoever made the file.
  • The result is too large to send. A merged PDF is roughly the sum of its parts. Choose File > Export, open the Quartz Filter menu and pick Reduce File Size, then check the result, because the filter softens images and small print can suffer.
  • A digital signature stops validating. A certificate-based signature is tied to one exact file. Merging produces a different file, so the signature no longer verifies. A signature that was drawn or placed on the page as an image stays part of that page.

Questions

Does merging change the PDFs I added?

No. Their pages are copied in. Only the document you merged into changes, which is why duplicating it first is worth the few seconds.

Can I merge PDFs and images together?

Yes. Drag an image file into Preview’s sidebar and it becomes a page. The Create PDF quick action also accepts a mix of images and PDFs.

How do I undo a merge?

Press Command-Z while the document is still open. After that, choose File > Revert To > Browse All Versions and pick the version from before the merge.