How to merge PDFs on this page
- Add your files. Drop them on the box at the top of the page, or click it and pick them from your file browser. You can add two files or twenty, and you can keep adding more after the first batch.
- Check the list. Each row shows the file name, its size, and its page count once that file has been read.
- Set the order. Drag a row to a new position, or use the up and down arrows at the right of the row. The remove button clears a file you did not mean to add.
- Merge. The button stays disabled until at least two PDFs are in the list, and its label tells you how many files it is about to combine.
- Download. The progress bar names each file as it is added. When it finishes you get the page total and the new file size, and the download saves as merged.pdf.
Only PDFs are taken in. A file is kept if your browser reports it as a PDF or its name ends in .pdf, and anything else is skipped with a short notice telling you how many files were left out. Everything runs inside this page on your own device, so your documents are never uploaded to a server.
How the ordering works
The list starts in the order your files arrive and is never re-sorted for you, so a file named "Appendix" will not quietly jump ahead of "Chapter 1". Position in the list is the only thing that decides the page order in the output: the first row's pages come first, then the second row's, and so on, with each file's own internal page order left alone.
Reordering or removing a file after you have already merged once clears the finished download automatically. That is deliberate, so you can never hand someone a file that was built from an older arrangement. Click merge again and you get a fresh one.
On a phone or tablet, dragging rows around is fiddly because touch screens and drag-and-drop do not always agree. The up and down arrows do the same job and are the reliable choice on a small screen.
What ends up in the merged file
Every page of every listed file, copied across as it stands. Nothing is re-drawn or re-compressed, so text stays real text that you can select, search and copy, and images arrive at the resolution they already had. Page sizes are kept as well, so a mix of Letter and A4, or of portrait and landscape, produces a document with mixed page sizes. That is normal and it prints correctly.
The merged document is assembled as a new file with your pages copied into it. Things that live at document level rather than on a page therefore do not travel across: the bookmark or outline panel and interactive form definitions are the two you are most likely to miss. If your source PDFs depend on either, open the result and check it before you send it on.
What merging will not do
This tool joins documents and nothing else. It will not shrink the result, remove pages, unlock a protected file, add page numbers or headers, or turn a scan into searchable text. Merged scans add their sizes together, so a stack of five 8 MB scans really is a 40 MB file. If the total is too big to email, run the finished document through Compress PDF once at the end rather than compressing each piece beforehand, and see why PDFs get so large for what is actually taking up the space.
When this comes in handy
- A cover letter and a resume that need to arrive as one attachment.
- A pile of receipts scanned one at a time, joined into a single expense report.
- A contract plus the signature page that came back separately.
- Chapters, exhibits or appendices assembled into one finished document.
- Photos or scans you turned into a PDF with Images to PDF and now want attached to a document you already have.
If something goes wrong
A file "could not be read." The notice names the file that failed and says it may be corrupt or password-protected. No merged file is produced, and your list is left intact, so you can remove that one row and merge the rest. A PDF with an open password cannot be read here at all: open it in your usual PDF viewer with the password, save an unprotected copy, and merge that copy instead.
A row shows a size but no page count. The page count is read the moment a file is added, so a missing count is an early warning that the same file will probably fail at merge time too. Re-exporting or re-downloading it usually fixes it.
The button reads "Add at least 2 PDFs to merge." Merging needs two or more files. To pull pages out of a single document instead, use Split PDF.
A big job stalls. Every file is held in your device's memory while it is combined, so several hundred megabytes of scans can be more than a phone will manage. Merge in smaller groups, or compress the heaviest pieces first.
Frequently asked questions
How many PDFs can I merge at once?
There is no file limit, page limit or watermark built into this tool. The real ceiling is your device's memory, because each file is read into memory as it is added. Desktop browsers handle very large jobs comfortably, while phones give up sooner on big scans.
Will merging lower the quality of my pages?
No. Pages are copied from one document into the other rather than re-rendered, so nothing is re-compressed at any point. Text stays selectable and searchable, and images keep the resolution they already had.
Can I reorder individual pages instead of whole files?
Not in a single step. Merge the files first, then open the result in Split PDF and choose the pages you want. Split always writes pages in ascending order, so to move one page to a specific spot, extract it on its own and merge the pieces in the order you want.
What happens to my original files?
Nothing at all. They are read, never written to. The merged document is a brand new file that lands in your downloads folder, and your originals stay exactly where they were.
Want the Mac Preview and Windows routes as well, for when you are not in a browser? The full walkthrough is here: how to merge PDF files.