How to Merge PDF Files Without Uploading Them

Why merge without uploading

A merged PDF often contains the most sensitive pages you have, such as bank statements, identity documents and contracts. When a website merges them for you on its server, a copy of each file travels over the internet and sits on someone else's machine, at least for a while.

When the merge happens in your browser, your computer does the work and the files are never sent anywhere. The result is the same PDF with one less thing to worry about. Our guide on checking whether a tool uploads your files shows how to verify this on any website.

Before you start

• Put the PDFs you want to merge in one folder, so that you can add them together.
• Keep the originals. The merge creates a new file and does not change them, but it is good practice to keep a copy.
• If a PDF needs a password to open, remove the password first with an unlock tool, because it cannot be merged while it is locked.
• If you have photos or scans as images, turn them into a PDF first, then merge the result with the others.

Step by step

1. Open the Merge PDF tool and drop your PDF files into the box, or click to browse. You can add more files later with the Add PDFs button.
2. Each file appears as a card with its first page, its name, its number of pages and its size. A file that cannot be read shows a message on its card instead.
3. Put the files in the order you want them. Use the Earlier and Later buttons under a card, or drag the cards.
4. Optionally click a card or Edit pages to open the pages of that file and change them. This is explained in the next section.
5. Check the summary in the sidebar, which shows how many PDFs and pages you are merging and the total size. Type the name you want for the new file.
6. Click Merge PDFs, then download the result. You can go back to editing if you want to change something and merge again.

Fix the pages before you merge

You do not have to merge whole files. Open a file to see all of its pages, and you can work on each page on its own.

• Rotate a page to the left or right, or rotate every page of the file at once.
• Delete a page you do not need. Undo delete brings the last page back, and Reset pages restores the whole file.
• Crop a page to a part of it. The cropped part is hidden when the file is viewed or printed, but the rest may still exist inside the file, so do not rely on cropping to remove sensitive information.
• Move a page earlier or later inside its own file. Pages move only within their own file, so to change the order between files, move the whole file.

What the merged file keeps and what it does not

The pages are copied into the new file, so text stays text and you can still select and search it. Nothing is turned into pictures, and the quality of each page is the same as in the original.

• Bookmarks, also called the outline or table of contents, are not carried over.
• Interactive form fields may not be kept, so fill in forms before you merge or save the filled form as a PDF first.
• The size of the new file is usually close to the total size of the files you added.
• Your original files are not changed.

If something goes wrong

• A file is shown with a red message: it may be damaged, or protected with a password. Remove the password or open and save it again with another program, then add it again.
• The browser becomes slow with very large merges. Merge in two or three smaller groups, then merge the results. Phones have less memory than computers, so use a computer for big jobs.
• The merged file is too big to email or upload. Use a compress tool on the result, and check how it looks afterwards.
• The pages are in the wrong order: go back to editing, move the files or pages and merge again. Nothing is lost.

A good habit for sensitive files

After you merge a set of private documents, store the result in a safe place and delete copies you no longer need, especially in downloads folders and chat apps. If you send the merged file by email, you can protect it with a password first.