How to Combine Two PDFs into One on Mac

You don’t need to install anything to combine PDFs on Mac. Preview, the default PDF viewer that ships with every Mac, can merge PDFs in a few clicks. Here’s how.

The fastest way: Preview’s thumbnail sidebar

1. Open the first PDF in Preview (double-click it in Finder)
2. View → Thumbnails (or press Cmd+Option+2) to show the sidebar
3. Drag the second PDF from Finder directly into Preview’s sidebar
4. Drop it where you want it (above or below the existing pages)
5. File → Export as PDF to save the combined file

The dragged PDF’s pages get inserted into the open PDF. Save and you have a single combined PDF.

Reordering pages

In the thumbnail sidebar, drag any thumbnail to reorder:

• Drag up/down within the sidebar
• The new order is reflected in the saved PDF

For more complex rearrangements, drag multiple at once (Cmd-click to select).

Combining three or more PDFs

Keep dragging additional PDFs into the sidebar. They append in the order you drag them.

For 5+ PDFs, the browser-based PDF Merger is often cleaner — it shows the full list and lets you drag-to-reorder more comfortably.

Selecting specific pages from each PDF

The sidebar approach combines whole PDFs. To pick specific pages:

1. Open the source PDF in Preview
2. Cmd-click the page thumbnails you want
3. Drag selected thumbnails into the target PDF’s sidebar

Only the selected pages get added. Useful for “I want pages 3-5 from this PDF in my final document.”

Save as PDF after merging

After combining, File → Export as PDF saves the merged file. The thumbnail sidebar’s reorganized state becomes the file’s actual page order.

Or use File → Save As (Cmd+S after holding Option key) for similar effect.

If you just close the window without explicitly exporting, Preview asks whether to save changes.

Browser-based alternative

For a more visual interface:

1. Open the PDF Merger
2. Drag PDFs into the upload area
3. Drag to reorder
4. Click Merge

Works the same on Mac but with a cleaner multi-file interface. Browser-based, no upload, fully private.

When to use which

Use Preview when:

• You only need to combine 2-3 PDFs
• You also want to reorder pages within
• You’re already in Preview

Use PDF Merger when:

• Combining 5+ PDFs
• You want a clean “drag files in order” interface
• You’ll do other operations afterwards (the browser-based workflow makes chaining easier)

After combining

Compress for email: PDF Compressor for smaller files.

Add OCR if scanned: PDF OCR for searchable text.

Split off sections: PDF Splitter to extract specific pages later.

Rotate sideways pages: PDF Rotator.

Common issues

Pages appear in wrong order: drag-reorder in the sidebar before exporting.

Some pages didn’t appear: Preview might have failed to import. Try opening the missing PDF first, then dragging again.

Output file is huge: each component’s full quality is preserved. Run through PDF Compressor.

Sidebar isn’t showing: View → Thumbnails (or Cmd+Option+2).

TL;DR

• Mac Preview: open one PDF → drag others into the thumbnail sidebar → File → Export as PDF
• Show thumbnails: View → Thumbnails or Cmd+Option+2
• For more PDFs: PDF Merger has a cleaner multi-file UI
• After: PDF Compressor, PDF OCR, PDF Splitter for follow-ups