When I need to merge PDF files online I usually use Sejda PDF. I like the fact that it’s online, so I don’t have to install anything locally. Works on any platform because it’s in a browser.
Sometimes I work with privacy sensitive files that I’m not allowed to upload to a third party service. So for peace of mind privacy I use their Sejda Desktop which works locally on my computer.
The simple scenario
When the requirements are simple: just merge the files, the task gets done in a few seconds.
Open the Online PDF Merge page and upload the PDF files. Drag and drop to reorder them and click Merge PDF. Once the task completes, click Download to save the combined result to your computer.
Generating a table of contents for PDF
If you’re merging multiple files, it’s handy to have a table of contents at the beginning of the combined PDF file, with links to the beginning of each of the merged documents. Helps navigating the combined document.
To have this table of contents generated for you click More options and then choose if you’d like to use the filenames or the document titles when building the TOC.
The simplest, yet not practical, is to just discard all existing bookmarks from the merged result.
The option I find most useful is to keep the existing bookmarks, but to wrap them underneath a bookmark per file. Each merged file gets a top bookmark, pointing at the first page, and has all the existing bookmarks from that file underneath.
Another option is to just create a bookmark per merged file, pointing at the first page of the corresponding document in the merged result.
Last but not least, one can also choose to keep all bookmarks as they are in the input documents also in the merged result.
Adding original filename to PDF page footer
This feature makes it easy to understand which PDF page was part of which original document when reading the merged PDF file.
Each page in the result PDF will have in the footer a line with the original filename or document title. To enable this, click More options and select Add filename to page footer.
Reordering and/or deleting pages when merging PDF files
Sometimes when I combine multiple PDF files need to shuffle few pages and reorder them.
Sejda has a nice visual tool to combine and reorder PDF pages. Each page is rendered as a thumbnail so you can easily tell which pages you want to work with. There’s a handy magnifier when you pause with the mouse over a thumbnail.
The size of the thumbnail can be increased or decreased to match your screen and comfort level.
Reordering PDF pages can be done by drag and drop. To reorder multiple pages at once first select all pages by clicking on them, then drag them to the right location.
Rotating PDF pages can be done inline by clicking on the rotate icons on each page thumbnail.
One can also delete PDF pages that should not be part of the final combined document by clicking the X in the top right of each page thumbnail.