Check the permissions of a PDF by choosing Tools > Show Inspector, then click the lock icon). Some encrypted PDF documents can't be merged, according to Apple.

Click Edit > Insert > Page from File (if the Page from File selection is dimmed so you can't click it, make sure that the file you have open is a PDF.

Select the thumbnail for the page where you want to insert the other document.

You'll see page thumbnails in the sidebar. On Mac, you can combine PDFs with a built-in tool found in Preview, according to Apple Support. Read more: How to download Windows 11 free How do I combine PDFs on Mac? You can save them as one PDF, or as individual PDFs.

Choose which individual pages or page ranges you want to pull out. To do that, select Split when the app opens. If you want to customize your merger a bit more, such as by changing the order of pages or only adding in certain parts of each PDF, you'll have to split them first.

Once your documents are in order, hit Merge, and name and save the new merged PDF.

You can also preview what the merged documents will look like. You have the option to move them up or down, or sort by name.

Click Add PDFs, and select however many you want to merge.

If you just need to merge two documents without changing the order of any pages, choose Merge.

Open the app, and choose Merge or Split.

It's available through the Microsoft Store for free. We tested a few, and found a solid option in PDF Merger & Splitter by AnywaySoft. If you're using Windows, you'll need a third-party app to help you combine PDFs.

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