How to merge PDF files, split one, and put its pages in order

Use a desktop PDF tool that edits pages: Preview on a Mac, PDFsam Basic on any computer, or Acrobat if you pay for it. Windows has no merge built in, though printing a page range to Microsoft Print to PDF will pull pages out. Online tools work too, but they upload the file.

30 October 2026 · 5 min read

What you are actually doing to the file

A PDF is a list of pages, each with its own content, plus things that belong to the whole file: bookmarks, links between pages, form fields and any digital signature. Merging, splitting and reordering move pages from one list to another. The page content survives untouched in any decent tool; the whole-file parts are what get lost or tangled, so it is worth knowing which of them your file has before you start.

On Windows, without installing anything

Windows can read a PDF in Edge but cannot combine two. It can take pages out of one: open the PDF, choose Print, pick Microsoft Print to PDF as the printer and type a page range such as 3-5. The new file holds those pages, but it is a printout: links, bookmarks and form fields do not come with it.

On a Mac, with Preview

Reorder: View, Thumbnails, then drag the pages in the sidebar.
Merge: open the first PDF, show thumbnails, and drag the second file from Finder into the sidebar where its pages should go. Save, or Export as PDF to keep the original.
Extract: drag a page’s thumbnail onto the desktop to make a one-page PDF of it.

Free and paid tools that do all of it

PDFsam Basic is free and open source, for Windows, Mac and Linux. It merges, splits by page, by size or by bookmark, rotates and extracts, and keeps the work on your computer.
Adobe Acrobat Reader is free but only reads; combining and organising pages needs a paid Acrobat plan.
qpdf is a free command-line tool. qpdf --empty --pages a.pdf b.pdf -- both.pdf merges, and qpdf --split-pages big.pdf page.pdf makes one file per page.
Online tools such as iLovePDF and Smallpdf are quick, but the file goes to their servers. For a contract, a payslip or anything with someone’s details on it, a desktop tool is the safer habit.

What can go wrong

Digital signatures break. Changing the pages of a signed PDF invalidates the signature. Merge copies, or merge first and sign last.
Forms collide. When two forms with the same field names are merged, the fields can end up sharing one value. Fill and flatten each form first, or keep them as separate files.
Bookmarks and links may be dropped or point at the wrong page after a reorder. Check them in the result.
Mixed page sizes are kept as they are, so an A4 letter merged with a US Letter scan prints each on its own size.
Size. A merged file is roughly the sum of its parts; a heavy scan does not get lighter by being merged.

Our own product, disclosed

Where our own software comes into this

We make Rutba Office, a free desktop suite for Windows. Its PDF app has a page strip down the side: drag a page to move it, turn a page that was scanned on its side, delete a blank one and undo it if you change your mind. Pages from another PDF can go in at any point, another file can be added to the end, one page can be extracted as a file of its own, and a file can be split in two. It saves to a new PDF, so the file you started from is left as it was, and nothing is uploaded anywhere.