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Merge PDF

Merge PDF files online in the order you choose: drag to reorder, see page counts, and download one combined PDF. Files never leave your browser.

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About the Merge PDF

Merge PDF joins several PDF files into one document, in the order you set. Drag the rows or use the arrow buttons to reorder them; each row shows a preview of the first page and the page count, so you can check the order before merging. Pages are copied as they are, so text stays sharp and selectable, and nothing is uploaded.

PDFs are processed in your browser with pdf-lib and PDF.js, so contracts, invoices and scans never leave your device.

How to use the Merge PDF

  1. Drop two or more PDF files onto the box, or choose them (up to 50 at once).
  2. Put the files in order by dragging the rows or using the up and down arrows.
  3. Optionally change the output file name.
  4. Click Merge PDFs and download the combined file.

Common mistakes

  • Expecting bookmarks to carry over. Merging copies pages, not each file's bookmark outline. Add bookmarks afterwards in a PDF editor if readers need to jump between sections.
  • Merging fillable forms. Form fields from several files can clash or stop being editable in the merged copy. Fill in and save (or print to PDF) each form first.
  • Mixing page sizes without checking. A Letter document merged with A4 pages keeps both sizes. That is correct, but it can surprise people who print the result; check the page sizes before sending.

Works well with the Merge PDF

Frequently asked questions

Is there a limit on file size or number of files?

You can merge up to 50 files of up to 150 MB each. The work happens in your browser, so very large documents depend on your device's memory; a laptop handles a few hundred pages easily.

Does merging reduce quality?

No. Pages are copied into the new file without being redrawn or re-compressed, so text, images and vector graphics are exactly as they were in the originals.

Can I merge password-protected PDFs?

Not directly. Open the file in your PDF reader with its password, save or print it as a new PDF without protection, then merge that copy.

Are my files uploaded?

No. The files are read and joined by your browser and the result is saved straight to your device.

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