Merge PDF files into one
The merge PDF tool combines two or more PDFs into a single file, with the pages in the order you dropped the files. It uses pdf-lib inside the browser tab, so the documents are never uploaded and no copy is left on a server.
Drop all the files at once and they become one job. Dropping them in separate batches starts a new job each time, so collect the set first.
Getting the order right
Pages come out in the order the files appear in the list before you confirm. If you select a folder's worth of files and drag them in, most operating systems hand them over alphabetically, so "01-cover.pdf", "02-body.pdf", and "03-appendix.pdf" land in sequence. Files whose names do not sort the way you want can be renamed first, or dropped one at a time in the right order.
Each source PDF is copied whole. Every page is included and nothing is reordered within a file. To leave pages out or pull out a range, run split PDF on that file first, then merge the piece you want.
Naming the output
The output name option sets the file name of the merged PDF. Leave it blank and the tool names the result after the first file with "-merged" added, so a batch starting with "contract.pdf" becomes "contract-merged.pdf". Type a name and the tool adds the ".pdf" extension if you leave it off. The field accepts up to 120 characters.
What is kept and what is not
The merged file is a new PDF assembled from the pages of the inputs. Page sizes and orientations are preserved per page, so a landscape page from one file stays landscape next to portrait pages from another. Text stays selectable where it was selectable before, so PDF to text works on the result, and images keep their original resolution.
Bookmarks and document-level metadata such as the title belong to the source documents rather than to their pages, and they are not carried into the merged file. Interactive form fields may not survive the copy. If any of those matter, keep the originals alongside the merged copy.
A password-protected PDF cannot be opened for merging. Remove the password in the program that applied it, then drop the file here.
File size
The merged PDF is roughly the sum of its inputs. Merging does not recompress images or fonts, so a set of large scans stays large. If the result is too big to email, there is no PDF compressor here, but you can render the heavy pages with PDF to images, shrink them with compress image, and rebuild them with images to PDF before merging.
Related tools
To combine images rather than PDFs, images to PDF puts each image on its own page and makes a PDF you can then merge here. To take a merged document apart again, split PDF writes one file per page or per range.
Frequently asked questions
How do I set the page order?
Files are merged in the order they appear in the list before you confirm. Dragging from a folder usually gives alphabetical order, so rename files if the sequence matters.
Can I merge only some pages of a file?
Not directly. Run split PDF on that file first to get the pages you want, then merge the piece here.
What is the merged file called?
Whatever you type in the output name field. Leave it blank and it is named after the first file with '-merged' added.
Does the text stay selectable?
Yes. Pages are copied as they are, so text that was selectable in the source is selectable in the merged file.
Are bookmarks and form fields kept?
Bookmarks and document metadata such as the title are not carried over, and interactive form fields may not survive the copy. Keep the originals if those matter.
Can I merge a password-protected PDF?
No. Remove the password in the program that set it, then merge.