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Merge PDF Files

Combine PDFs into one document. Drag the cards to set the order, then merge. The files stay on your device.

  • Unlimited
  • No signup
  • Private
  • Works offline

Arrange and merge PDF files

No PDFs yet

Keep every page the size it is, or make them all match.

Add at least one PDF

How it works

  1. 01

    Add your PDFs

    Drop them in any order, from anywhere on disk. Encrypted files are flagged, not silently skipped.

  2. 02

    Set the order

    Drag a card, use the arrows, or sort alphabetically. Remove a file if it does not belong.

  3. 03

    Merge and download

    One PDF out, with optional bookmarks marking where each source file begins.

What merging preserves

Merging copies page objects across rather than re-rendering them, so text stays selectable, vector artwork stays sharp and embedded fonts come along unchanged. Page sizes are kept by default: an A4 report and a US Letter appendix can share one document at their own sizes. Or normalise everything to one size.

Two things change. Interactive form fields with the same name would collide across files, so flattening them is an option. File-level metadata cannot be merged, so the output takes the title you give it. Digital signatures do not survive a merge. That is how the format works: the signed byte range no longer exists.

Files per merge
Unlimited. Order is entirely yours.
Page count
No cap. 1,000-page merges work, they just take longer.
Encryption
Password-protected PDFs need unlocking first.
Bookmarks
One outline entry per source file, marking where it begins.

Frequently asked questions

Are my PDFs uploaded to be merged?
No. The merge runs in the page with pdf-lib, so the documents are read from disk into memory and written back out as a download. Confidential files never travel over the network.
How many PDFs can I merge at once?
There is no fixed file count. Available browser memory is the practical limit, and a 1,000-page merge is supported.
Can I reorder the pages inside a file?
This workspace changes file order. Use Organise PDF when you need to reorder or delete individual pages.
Does merging reduce quality?
No. Existing page objects, text and images are copied rather than rendered again.
Can I merge password-protected PDFs?
Protected documents need to be unlocked before they can be parsed and merged.
Will bookmarks and links still work?
Links remain intact, and the merged document gets one bookmark per source file marking where it begins.

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