UBUseBrowserTools

Merge PDF

Combine two or more PDF files into one document, free and entirely in your browser. Reorder files, merge in one click, and download instantly — no uploads.

100% private — runs in your browser, nothing is uploaded

Choose PDF files or drag them here

Add two or more PDFs — they'll be combined in the order below

What does this Merge PDF tool do?

It combines two or more PDF files into a single document, in exactly the order you choose. Each page is carried over as-is — text, images, fonts and page sizes are copied without re-rendering or re-compressing anything, so the merged file looks identical to the originals. You can mix files with different page sizes and orientations freely; every page keeps its own dimensions.

How to merge PDF files

  • Click the upload box (or drag files onto it) and pick two or more PDFs.
  • Check the list: each file shows its page count and size once it has been read.
  • Use the arrow buttons to put the files in the order you want them to appear.
  • Click "Merge PDFs", then download the combined file.

How it works — merging inside your browser

Most online PDF mergers upload your documents to a server, process them there, and make you trust that they are deleted afterwards. This tool works differently: a small PDF library runs directly in your browser tab, opens each file locally, copies its page objects into a new document, and assembles the result on your own device. Your files never travel over the network, there is nothing to delete from anyone's server, and the merge works even if you go offline after the page has loaded.

Tips and limits

  • Password-protected files can't be merged directly — remove the password first with the Unlock PDF tool.
  • There is no fixed limit on the number of files or pages; very large merges are only limited by your device's memory.
  • Interactive extras such as bookmarks and form fields may not survive merging; regular page content always does.

When would you merge PDFs?

Typical cases: sending a single attachment instead of five (invoices and receipts for your accountant), assembling scanned chapters into one book, packaging a CV with certificates for a job application, or attaching annexes to a signed contract. One combined file is easier to email, print and archive than a folder of fragments.

Frequently asked questions

Are my PDF files uploaded to a server?

No. The files are opened and merged by JavaScript running in your browser tab. They never leave your device, which also means there are no copies on a server to worry about.

How many PDFs can I merge at once?

There's no fixed cap. Merging a handful of files with hundreds of pages is routine; the practical limit is your device's memory, since the whole merged document is assembled locally.

Will merging reduce the quality of my PDFs?

No. Pages are copied object-by-object rather than re-rendered, so text stays sharp and images keep their original resolution. Note that bookmarks and interactive form fields may not carry over.

Can I merge password-protected PDFs?

Not directly — a protected file can't be read without its password. Remove the password first using the Unlock PDF tool, then merge the unlocked copy.

Can I control the page order?

Pages follow the file order shown in the list: all pages of the first file, then the second, and so on. Use the up and down arrows to rearrange files before merging.

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