Merge PDFs on Windows without Acrobat

Windows opens PDFs, but it has no way to combine two of them into one. This is how to do it with a small app, without Adobe Acrobat and without uploading the files to a website.

What Windows already has

Windows opens PDFs in Microsoft Edge, which can show, print and mark them up. It can't merge files or move pages from one into another. Adobe's free Acrobat Reader can't either: combining files needs the paid version. Websites will merge PDFs for free, once you've uploaded them.

Merging with PDF Assembler

1. Install PDF Assembler from the Microsoft Store. It runs on 64-bit Windows 11, and on Windows 10 from version 1809.
2. Open it and drag the PDFs from File Explorer onto the window, or click the drop area to choose them. Images and text files can go in too, and become pages.
3. Click Next and drag the files into order. The one at the top becomes the first page.
4. Click Next again and click Save PDF: everything goes into one PDF.

You can skip step 2. On Windows 11, select the files in File Explorer, right-click them and choose Combine with PDF Assembler: they open together in a new window. Or copy them in File Explorer and press Ctrl+V in the app, which also takes an image copied from a browser or a screenshot.

It all works from the keyboard too. The arrow keys move through the list, Ctrl with an arrow moves the selected file up or down, Delete removes it, and Ctrl+Z undoes any of it.

Moving single pages

To put a few pages of one file into the middle of another, switch the list from Files to Pages. It shows every page of the finished document as a thumbnail, captioned with the file it came from. Drag pages anywhere, rotate a sideways scan, and delete what you don't need.

Password-protected PDFs

A protected PDF shows a lock in the list. Click it and type the password to include the file. The merged PDF has no password unless you give it one: on the Save step, open Advanced options, set Protect to Standard (AES-128) or More secure (AES-256), and type a new password.

What differs on Windows

The Windows and Mac versions do the same things, with three main exceptions on Windows. HEIC photos, the iPhone's default format, can't be added, even on a PC that opens them itself, while the Mac version adds them. RTF documents keep only their text. And Arabic, Hebrew, Hindi or Thai text isn't laid out correctly; the app warns you when a file has it. Photos you add also become pages a little differently: at Original, Windows re-encodes a JPEG at a high quality instead of copying it as it is, and converts colours to standard sRGB.

Buying it

You buy PDF Assembler once in the Microsoft Store, with your Microsoft account. There's no subscription, and the app itself has no account or sign-in. It makes no network requests, so it works offline too.

About PDF Assembler

PDF Assembler is a small app for macOS and Windows that merges, splits, compresses and password-protects PDFs on your own computer. It makes no network requests at all. It's paid once, with no subscription, and the store links are on the product page.

Other guides: Combine photos into one PDF, Make a PDF smaller without uploading it.