How to Merge PDF On Mac
macOS includes built-in PDF merging through Preview, making it one of the few operating systems where you can combine PDFs without extra software. However, Preview's approach has limitations—it modifies the original file, offers no compression, and doesn't support batch operations. For quick two-file merges, Preview is convenient. For anything more complex, SublimePDF's online tool provides reordering, selective page merging, and file size optimization.
Follow the step-by-step instructions below, then use the free tool directly — no registration or download required.
Open Tool →How to Merge PDF On Mac — Step by Step
Quick merge with macOS Preview
Open your first PDF in Preview. Show the sidebar (View > Thumbnails). Open a second PDF in another Preview window. Drag page thumbnails from the second window into the first window's sidebar at the position where you want them inserted.
Save correctly in Preview
Critically, use File > Export as PDF (not File > Save) to create a new merged file. Using 'Save' overwrites your original document with the merged version, which you may not want.
Merge with SublimePDF for more control
Open SublimePDF's Merge PDF tool in Safari, Chrome, or any Mac browser. Upload all PDFs you want to combine—there's no limit on the number of files.
Reorder and select pages
Drag file thumbnails to set the order. Expand any file to see individual pages and exclude ones you don't need. This selective merging isn't possible in Preview without manually deleting pages first.
Merge and download
Click 'Merge' to combine everything into a single optimized PDF. The output is often smaller than the combined original files because SublimePDF removes duplicate fonts, resources, and metadata during merging.
Pro Tips
- 💡 Preview's drag-and-drop merge works best for combining 2–3 simple documents. For 4+ files or documents with complex formatting, use SublimePDF to avoid Preview's occasional rendering issues.
- 💡 In Preview, you can also drag individual JPG, PNG, or TIFF images into a PDF's thumbnail sidebar—they're automatically converted to PDF pages.
- 💡 If Preview's merge produces a file with incorrect page sizes, it's because the source PDFs had different dimensions. SublimePDF handles mixed page sizes more reliably.
- 💡 For recurring merge tasks on Mac, create a Quick Action in Automator that opens SublimePDF's merge tool—you can trigger it from Finder's right-click menu.
Privacy & Security
All processing happens directly in your browser. Your files are never uploaded to any server — they remain on your device throughout the entire process. SublimePDF uses WebAssembly technology for fast, secure, client-side processing.
Works Everywhere
This tool works on any modern browser — Chrome, Firefox, Safari, or Edge — on desktop, tablet, or mobile. No software to install. PDF is an open ISO standard supported by all major platforms.
How to Merge PDF On Mac — FAQ
Can I merge PDFs with Preview without modifying the originals?
Why does my merged PDF from Preview have larger file sizes?
Does Finder's Quick Actions include PDF merge?
Can I merge password-protected PDFs on Mac?
Related Guides
How to Merge PDF Files Online
Merging PDF files is one of the most common PDF tasks — whether you're combining reports, contracts, or scanned pages into a single document. SublimePDF lets you merge PDFs instantly in your browser with no file uploads to any server.
How to Merge PDF On Windows
Windows doesn't include a native PDF merging tool—Microsoft Print to PDF can create PDFs but can't combine them. Most Windows users resort to paid software like Adobe Acrobat or random free tools bundled with adware. SublimePDF's web-based merge tool works in any Windows browser (Edge, Chrome, Firefox) with no installation, no ads, and no file size surprises. For power users, PowerShell and command-line options also exist.
How to Merge PDF On iPhone
Combining multiple PDFs on your iPhone is essential when you need to submit a single document from several files — like merging scanned receipts, consolidating travel documents, or assembling application materials on the go. While the iOS Files app lets you create PDFs from images, it lacks a true merge function. SublimePDF works directly in Safari on your iPhone, letting you drag, reorder, and merge PDFs without installing any app.