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Merge PDF files.

Combine ordinary, unencrypted PDFs in a chosen order and download a new file. The merge runs in your browser; the tool supports mixed page sizes but may not preserve bookmarks, interactive forms, or signature validity.

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How to use Merge PDF

Merge PDF copies the pages from each selected source into one new document. It keeps each page's own dimensions, so Letter, A4, and other page sizes can appear together in the output. It is useful for joining reports, handouts, or separately prepared sections without changing the text on those pages.

Steps

  1. 1Choose up to 20 valid, unencrypted PDFs, each no larger than 50 MB and 200 MB combined.
  2. 2Review the detected page counts and arrange files in the exact sequence you want.
  3. 3Merge the selection. The browser limits the resulting document to 500 pages.
  4. 4Download the new PDF, reopen it in a PDF reader, and check section boundaries and page count.

Privacy: The merge worker reads file bytes in this browser and creates the result in browser memory. The application does not send the selected PDFs to a PDF processing endpoint. Your browser's download settings determine where the result is saved.

Supported scope: The workflow accepts up to 20 files, 50 MB per file, 200 MB combined, and 500 pages total. It copies page content and does not claim to preserve outlines/bookmarks, interactive form behavior, layers, every annotation, or digital signature validity. A rewrite can invalidate signatures. Very large files may also be constrained by device memory.

Merge PDF FAQs

Can I change the file order?
Yes. Use the move controls beside each file before you merge; the resulting pages follow that displayed file order.
Do mixed page dimensions work?
Yes. Each copied page retains its own page size. A merged document can therefore contain pages with different dimensions and orientations.
Are bookmarks and form fields preserved?
Do not rely on that. The current merge implementation copies pages and their page content, but does not promise to retain document outlines or interactive form behavior.
Will a signed PDF stay signed?
The source file is not edited, but merging creates a rewritten output. Existing digital signatures should be treated as invalid in the merged copy.
What if my files are too large?
Each file must be 50 MB or smaller, the combined selection no more than 200 MB, and the total no more than 500 pages. A device can run out of memory before reaching those limits; try smaller selections if processing fails.