How to merge PDF files without uploading them

A contract, an invoice and the photos of a signed form often have to become a single PDF. The quickest search result is usually a website that asks you to upload all of them. You can do the same job on your own computer. Five ways, and where each one stops.

1. Mac: Preview

Open the first PDF in Preview and show the thumbnails in the sidebar (View menu). Drag the other PDFs or images from Finder into the sidebar, where you want them, then drag the thumbnails to change the order. Save a new file with the Export as PDF command of the File menu.

Good for: any Mac, nothing to install, and you see every page while you sort.

Where it breaks: it only exists on a Mac. If you simply save, the pages are added to the first PDF itself, so make a copy first or use Export as PDF. With many files, dropping each one in the right place takes a while.

2. Windows: only for photos

Windows has no built-in tool that merges PDF files. For photos there is a workaround: select the images in File Explorer, right-click, choose Print (in Windows 11 it is under Show more options) and pick the printer called Microsoft Print to PDF. You get one PDF with one photo per page.

Good for: turning a few scans or phone photos into a single PDF on a computer where you cannot install anything.

Where it breaks: it does not work with existing PDFs. The order follows the files, not your choice, and the print layouts may crop or shrink the photos.

3. A free desktop program: PDFsam Basic

PDFsam Basic is free and open source, for Windows, macOS and Linux. Its Merge tool takes a list of PDFs, lets you choose page ranges for each one, and writes the result without any connection. If you use the command line, qpdf does the same in one line:

qpdf --empty --pages first.pdf second.pdf -- merged.pdf

Good for: merging often, large batches, and other jobs such as splitting or rotating.

Where it breaks: you have to install a program, which many work and school computers do not allow. It merges PDFs only: photos have to be turned into PDFs first.

4. Online PDF tools

Websites that merge PDFs work in any browser: you upload the files, put them in order and download the result.

Good for: a one-off on a borrowed computer, when the documents are not private.

Where it breaks: your files go to someone else's server, which is a problem for IDs, contracts, payslips or medical papers. Free plans often limit the size, the number of files or the tasks per day, and some ask you to sign up or pay only after you have done all the work.

5. A browser extension: the website experience, on your computer

An extension can do the job in a page of your browser, so the files are never uploaded. We make one, Ordelio PDF Merge (free, no file or page limits):

1. Click the extension icon: the merge page opens in a new tab.
2. Drop your PDFs and images on it, or paste a screenshot with Ctrl+V. Drag the cards to put them in order and rotate the ones that need it. To keep only some pages of a PDF, type them in its Pages box, for example 1-3, 5.
3. Click Merge and download: the new PDF is saved in your downloads.

JPG, PNG, WebP, GIF, BMP and AVIF photos become pages next to your PDFs, the right way up, in A4, Letter or the size of the image. An option makes large photos smaller for email.

Where it breaks: it shows no page previews of the PDFs, so you choose pages by number. Password-protected PDFs and iPhone HEIC photos have to be converted first (it tells you how). It is available for Microsoft Edge and Firefox, not yet for Chrome.

In review: Microsoft Edge Add-ons, Firefox Add-ons.

Which one to use

In short: on a Mac, Preview is already there. For large batches every week, install PDFsam. For private documents on any computer with Edge or Firefox, merge them in the browser without uploading anything.

Found a file that none of these methods handles? Tell us, we read every message.