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PDF Merger

Merge two or more PDF files into one merged.pdf in your browser, in the order you set with move up/down. Pages keep size and rotation. No upload.

Your inputs and files stay in your browser

Drag and drop PDF files here

or choose a file from your device

On this page

Combine two or more PDF files into a single merged.pdf in the browser and set the order with the move up and move down buttons. Your documents stay on your device.

Detailed Functionality

Pages are appended in list order: all pages of the first file, then all pages of the second, and so on. Each page keeps its size, rotation, crop box and resources such as fonts and images, so it looks exactly like in the source. Add files by dropping them, with Choose files or with Add files; the same file can be added more than once.

The first file is the base of the result: its bookmarks, form fields and document properties are kept, while those of the other files are not merged — their pages are added as plain pages. Merging runs in a Web Worker with Rust/WebAssembly (lopdf), so the page stays responsive.

A damaged or password-protected file is named in the error message and marked in the list. The whole result is built in memory, so very large sets are limited by the browser's available RAM.

Practical Examples

Cover and report: cover.pdf (1 page) followed by report.pdf (2 pages) gives a 3-page merged.pdf with the cover first.

Change the order: press Move up on the last file to move it one place higher; the list order is the page order of the result.

Locked input: if one file needs a password to open, merging stops with “locked.pdf: the PDF is password-protected and can't be processed.” and that row is marked Error.

Only one file: with fewer than two files Merge PDFs stays disabled and the hint “Select at least 2 PDF files to merge.” is shown.

How to Use This Tool

  1. Add PDF files

    Click Choose files or drop PDFs onto Drag and drop PDF files here. Use Add files to append more later.

  2. Set the order

    Use Move up and Move down on each row; remove a file with Remove file or start over with Clear all.

  3. Merge

    Click Merge PDFs (it needs at least two files).

  4. Download

    When “PDFs merged successfully!” appears, check the size and click Download to save merged.pdf.

Tips and Best Practices

  • Put the file whose bookmarks and form you want to keep first — only the first file's document-level data survives.
  • Pages are copied as they are: nothing is re-compressed, so the result is about the sum of the inputs; run it through PDF Compressor if needed.
  • Remove the password from protected files before merging.
  • Changing the list after a merge hides the old result; merge again to get an updated file.