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Merge PDF files

Join contracts, invoices, scans and reports into one PDF in seconds. Put the files in any order and take only the pages you need from each. Merging happens in your browser, so your documents are never uploaded.

  • Free
  • No sign-up
  • Private — runs in your browser

How do I merge PDF files?

  1. 1Choose your PDF files, or drag them onto the box.
  2. 2Put them in order: drag the handle or use the up and down arrows.
  3. 3Optional: under a file, type the pages to take from it, such as 1-3, 5.
  4. 4Press Merge PDFs and download merged.pdf.

How does merging PDFs work?

  1. 01Merged PDF = pages of file 1 + pages of file 2 + … in list order
  2. 02Pages taken from a file = all pages, or the ranges you type ("1-3, 5, 8-")
  3. 03Total pages = sum of the pages taken from each file

A PDF is a set of pages, and each page carries its own text, pictures, fonts and size. Merging copies each chosen page — with everything it needs — into a new PDF, one file after another. Pages keep their own size and orientation, so an A4 letter and a Letter-size form can sit in the same file.

Because the pages are copied rather than printed or re-scanned, nothing is re-compressed: text stays sharp and selectable, and images keep their quality. Links inside a page usually keep working; bookmarks and fillable form fields from the original files are not carried over.

The merge runs entirely on your device using the open-source pdf-lib library. Your files are read in the browser's memory and the new PDF is saved straight from there — nothing is sent to a server, which makes it safe for bank statements, contracts and ID documents.

Good to know

  • Need only some pages? Type them under each file instead of splitting the files first.
  • Name files 01, 02, 03… before adding them so they arrive in the right order.
  • Merging a scan with a large file size? Compress the result afterwards if a form limits uploads to a few MB.
  • Check page counts in the list before merging — a file showing fewer pages than expected may be damaged.

Merge PDF — common questions

Are my PDFs uploaded to a server?

No. Merging happens inside your browser on your own device. Your files are never sent anywhere, and nothing is stored after you close the page.

Does merging reduce quality?

No. Pages are copied exactly as they are, so text, pictures and vector drawings keep their original quality, and text stays searchable.

Can I merge password-protected PDFs?

No. Encrypted PDFs can't be read without unlocking them. Open the file in your PDF reader, save or print it as a new PDF without protection, and merge that copy.

Can I choose which pages to include?

Yes. Under each file, type the pages you want, like 1-3, 5 or 8- (page 8 to the end). Leave it empty to include every page.

Is there a limit on files or size?

There is no fixed limit and no watermark. Very large files (hundreds of MB) depend on your device's memory and may be slow on a phone.

Are bookmarks and form fields kept?

The pages and their content are kept, and links on a page usually work. Bookmarks (the outline) and fillable form fields from the original files are not carried over.

Sources

Formulas last reviewed: September 30, 2026 ·How we check our formulas

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