Combining pdf documents on an Apple computer is easy. Leopard, Snow Leopard, Lion and Mountain Lion (the latest versions of Macintosh OSX) all have the ability to merge two different pdf documents together and even move pdf pages within a pdf file. There are lots of websites offering to sell software to do it, but you don’t need a third party program to do it – it’s built right in to OS X for free. Things have changed to make it a little easier with Mountain Lion so I’ve made a new post on merging two pdfs in Mountain Lion here, but for OSX prior to Mountain Lion, just follow the instructions below!
To join two or more pdf files together using Preview (the standard pdf viewer in OS X) simply open the pdf file in preview, open the thumbnail view (Shift-⌘-D), and then drag a second pdf ON TOP OF an existing page thumbnail. (It must be on top of the thumbnail, see the pictures below). The two documents will merge into one. Then save the new combined file. Read on for step-by-step instructions.
SUMMARY: To combine two separate PDF files into one document you need to drag the new pdf ON TOP OF an existing thumbnail until the double grey border appears – then it will merge the two pdfs together. (You can then save the new merged pdf.) If you drag it into the sidebar but not on top of an existing page the new file will be added as an external link – not merged into the original pdf document. See these two pictures below to visualise the difference.
Here’s how to do it step by step.
1. Firstly, open one of the pdf files in Preview. Preview is the default application that a pdf will open into so if you just double click on the pdf file it will open in Preview.
2. Now go to the menu at the top of the screen called ‘View’ and click on ‘Sidebar’ (or ‘Show Sidebar’ if you have Snow Leopard). Alternatively, press Shift-Command-D to show the thumbnails. This will make a sidebar appear on the right side of the window with thumbnails of all the pdf pages in it. (See these pictures below).
3. You can now drag the second pdf file (from a folder or from your desktop) or even a page from within the second pdf file (from thumbnail view) into this sidebar window, and it will be added to your pdf document as an additional page.
To merge the two files you need to drag the new pdf ON TOP OF an existing thumbnail. (You will get a double grey border. See these two pictures below.
In older versions of Preview like Leopard,you get a red line to show you it will not be merged.
With Snow Leopard you get a blue bar.
In Lion no lines appear.
In all cases you do get the little grey box when you are merging and the same principle applies – drag it on top of the existing thumbnail to merge the two documents.
You can now save it – use ‘save as’ to save a new document with the merged fles, or you can use use ‘save’ to save over the existing document, adding the new pages to it.
An alternate way if you have lots of pdfs to merge.
Here’s an alternate way suggested in the comments below. It’s much faster if you have multiple files to merge.
Mac OS X Lion
From “Finder”, select and click all the pdf’s you want to assemble.
This will open them all at once in “Preview”.
Pick the “File” dropdown menu .
Pick the “Print” dropdown menu.
In the lower left hand corner, click the arrow next to “PDF”.
Click “Save to PDF”.
This will save all the separate pdf files into one pdf document.
Here are some more Macintosh How To articles to do with pdf documents:
Click here for how to reduce the file size of a pdf file.
Click here for how to edit a pdf document.
Click here to for how to make a pdf booklet.