Mac 合并 PDF：3 个免费方法 / Mac PDF Merge: 3 Free Methods

A Mac PDF merge does not require paid software, though Adobe has done a good job of leaving that impression. Automator ships with macOS and builds a reusable Quick Action, qpdf from Homebrew handles a whole directory in one line, and a browser-based local tool works without a page cap. All three are free and none of them uploads anything. They differ by scale: a couple of files now and then, a batch that comes back every month, and a several-hundred-page job needing page selection each have a route that fits.

What free covers when you merge PDFs on a Mac

Free here means no payment and no upload. Not one of these three needs an account, and not one sends your files to somebody else's server. What an Acrobat Pro subscription actually buys is OCR, batch form handling and signature workflows. For plain concatenation it is not better than the three options below.

Three things decide which one to use: page count, whether the order needs adjusting, and whether you need to pick pages. Answer those first and you avoid installing a tool, finding it awkward, then starting over.

Method 1: an Automator Quick Action you build once

Automator comes with macOS, and a Quick Action you save stays in the Finder right-click menu. It suits anyone who merges the same set of documents every month.

• Open Automator, create a new document, and choose Quick Action.
• Set the header to: workflow receives PDF files in Finder.
• Search for Combine PDF Pages and drag it into the workflow area.
• Tick the reorder option if you need it, then save under a name such as Merge PDFs.
• From then on, select several PDFs in Finder, right-click, choose Quick Actions, then your saved action.

Its weak point is ordering. The sequence follows the selection order, and Finder sorts names as text, so scan-2 lands after scan-10. Rename first if the order matters. It also struggles with very large files; a few hundred pages can stall it.

Method 2: qpdf in Terminal, built for batches

Install once with brew install qpdf. Merge with one line: qpdf --empty --pages a.pdf b.pdf c.pdf -- out.pdf.

--empty tells qpdf to start from nothing and take pages only from the files listed after it. For page ranges, write qpdf --empty --pages report.pdf 1-5 appendix.pdf 1-z -- out.pdf. qpdf does not re-encode page content, so the output stays close to the sum of the inputs, and bookmarks carry across.

For a batch, qpdf --empty --pages *.pdf -- out.pdf combined with a short for loop pins the order down. The entry cost is the command line; the payoff is repeatability. Put it in a script and next month's twelve reports take no effort.

Method 3: a browser-based local tool for big files and page picking

Open PDFMergeNext in Safari or Chrome, choose your files, drag them into order, merge, download. The merge runs on WebAssembly inside the browser tab, so nothing leaves the Mac. This route fills the gaps left by the other two: no page cap, large drag handles instead of guessing from filenames, and page selection written directly as 1-3,5.

The three free methods side by side

Method	Setup	Page cap	Reorder	Page picking	Scriptable
Automator Quick Action	None, built in	Stalls at a few hundred	By renaming	No	No
qpdf in Terminal	One brew install	None	Specified in the command	Yes, 1-5	Yes
Browser local tool	None	None	Drag handles	Yes, 1-3,5	No
Upload website	None	Usually capped	Yes	Partly	No

The last row is there for comparison only. Upload sites are free too, but the files cross somebody else's server. Contracts, medical records and anything carrying names should not take that route.

When to stop merging PDFs on Mac without Acrobat

• You need OCR. A scan is an image, and making the text searchable is outside what Automator and browser tools do.
• You need batch work on form fields. Merging fillable PDFs without colliding field names is where paid tools genuinely earn their price.
• You need an audit trail. Free tools do not record who merged which files and when, so regulated work needs a separate process.

Outside those three, concatenation is not worth paying for. If the order keeps going wrong, read naming conventions for merging PDFs first. For page selection syntax, see picking pages with 1-3,5.