How to merge PDF files

Merging is the most common PDF task there is: a scanned form and its cover letter, a contract and its appendix, six invoices that should be one attachment. The only thing that usually goes wrong is the order.

Open Merge PDFCombine documents into one, in your order

Step by step

  1. Add every file

    Drop all the PDFs onto Merge PDF at once, or add them one at a time — both work, and you can keep adding after the first drop.

  2. Put them in the right order

    Each file appears in a list. Drag them into the order you want the finished document to read, and remove anything you added by mistake before running the merge.

  3. Merge and download

    One click joins them into a single PDF. Pages keep their original size and orientation, so a portrait letter followed by a landscape table stays exactly that.

Merging does not re-compress anything

The pages are copied across as they are, so nothing is re-encoded and no quality is lost. It also means the merged file is roughly the sum of its parts — if that comes out too large to email, run it through Compress PDF afterwards rather than merging differently.

Mixed page sizes are fine

A merged document can contain A4, Letter and landscape pages together. If you would rather they all matched, Resize PDF can bring the finished file onto one paper size.

Common questions

How many PDFs can I merge at once?

Up to 30 files in a single merge, within the 200-page and 80 MB limits.

Does merging change the quality?

No. Pages are copied without re-encoding, so text stays sharp and images are untouched.

Can I merge a scanned PDF with a normal one?

Yes. Merging works on the page level and does not care whether a page contains real text or a scanned image.

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