How to Merge PDF Files Online for Free

Published by PdfEdit+ on October 19, 2026

To merge PDF files, add them to Merge PDF, drag them into the order you want, select Merge All, and download the combined file. You need at least two PDFs, and each one can be up to 50 MB.

The files are combined in your browser on your own device, so they aren’t uploaded to a server. This guide covers the steps, how to get the order right, what to check in the finished file, and what to do when something goes wrong.

When merging PDFs is useful

Merging is worth doing whenever someone expects one document but you have several. Common examples:

An application that asks for a single upload: a cover letter, CV, and certificates in one file.
A month of invoices or receipts collected into one PDF for an accountant.
A document scanned in batches, where each batch was saved as a separate file.
A report whose chapters were written and exported by different people.

One file is easier to email, upload, print, and archive, and the reader sees the pages in the order you intended.

How to merge PDFs step by step

Open Merge PDF.
Drag your PDFs onto the upload area, or click it to choose files. You can select several files at once and add more later. Each file appears as a card showing its first page, its position (#1, #2, and so on), and its size.
Drag the cards into the order you want. Card #1 becomes the start of the merged document.
Optional: use the eye icon to open a file in a new tab and check it, or the bin icon to remove it.
Select Merge All. The button is available once at least two files are added.
Download the result. It is saved as merged.pdf, so rename it to something descriptive before you share it.

Getting the order right

The merged PDF follows the order of the cards exactly: every page of file #1, then every page of file #2, and so on. Pages inside each file keep their original order.

Check the numbers on the cards. When you select several files at once, your device decides the order they arrive in, and it isn’t always alphabetical.
Number your files first if you merge the same kind of document often, for example 01-cover.pdf, 02-report.pdf. It makes the right order easy to spot.
If you can’t drag the cards on your device, remove a file with the bin icon and add it again. Newly added files always go to the end of the list.

How to check the merged file

Before you send the merged PDF, open it and check:

Page count. It should equal the pages of all the original files added together.
The joins. Look at the last page of each original file and the first page of the next one. This is where an ordering mistake shows up.
Page size and orientation. Each page keeps its original size and orientation, so a landscape page stays landscape between portrait pages. That is expected.
Text and links. Text stays selectable and searchable, and web links keep working.

Some things belong to a whole document rather than to its pages, and they are not carried over:

Bookmarks (the outline or table of contents in a viewer’s sidebar).
Fillable form fields. A form stops being fillable after merging. If a form must stay fillable, send it as a separate file.
Document properties such as the title shown in some viewers.

Common problems and fixes

Merge All is greyed out. Add a second PDF. A merge needs at least two files.
“… could not be merged”. The message names the file that failed. That file usually isn’t a valid PDF or is damaged. Open it in a PDF viewer; if it opens, save or export it as a new PDF and try again.
“File too large”. Each file can be up to 50 MB. Split a very large file into smaller parts first.
The merged file is very large. Its size is roughly the sizes of the originals added together. If it holds scanned pages, compressing it can help.
It’s slow on a phone. The work happens on your device, so big files take longer on older or busy phones. Close other tabs, or merge fewer files at a time.

Try it

Open Merge PDFCombine PDFs in your browser. No signup.