PDF Merger
Merge multiple PDF files into one document in your browser for reports, submissions, document packages and archiving.
Your result will appear here.
PDF Merger online
Merge several PDF files into one, in the order you choose — assembled locally with pdf-lib, so the documents never leave your device.
How to use this tool
- Choose two or more PDF files.
- Arrange them in the order their pages should appear in the combined file.
- Click Merge and download the combined PDF.
Common uses
Joining a contract and its annexes into one file for signing, combining monthly statements into a yearly bundle, merging scanned chapters into a single document, and meeting upload forms that accept exactly one PDF.
How it works
The merger uses pdf-lib to copy every page of every input into a new document, in the order given. Page content is copied as-is — text stays text, links and annotations largely survive, and nothing is rasterised — so the merged file is as crisp and searchable as its sources. What merging does not do is reconcile the inputs: differing page sizes stay differing, and document-level features tied to a single file (its outline/bookmarks, form state) are not rebuilt across the combined set. The page order is entirely yours; the tool imposes nothing.
Worked example
A main agreement of 6 pages, a pricing annex of 2 and a signed cover sheet of 1 merge into a 9-page PDF in the order cover, agreement, annex if you list them so. Drag the cover sheet last instead and the same three files produce a document that opens on the agreement — same inputs, different story — which is why a ten-second order check beats a re-merge.
Privacy and browser processing
Your PDFs are merged in your browser with pdf-lib — the files are never uploaded or stored.
Frequently asked questions
Why did the bookmarks disappear?
Outlines belong to a document, not to its pages, and page-copying merge does not rebuild a combined outline. If the merged file needs navigation, add bookmarks afterwards in a PDF editor, or merge with tooling that reconstructs the outline tree.
Do form fields and signatures survive?
Page content copies faithfully; interactive form fields are copied in a basic form and digital signatures do not survive merging — a signed PDF merged into another file loses its cryptographic validity, since the signed bytes changed. Keep signed originals separate and merge unsigned copies.
Can I merge password-protected PDFs?
Encrypted inputs cannot be read by the library in the browser. Remove the password first (with the owner's consent and the password in hand, any PDF editor can save an unprotected copy), then merge.
Is there a file size limit?
Your device's memory is the practical ceiling — dozens of ordinary documents merge comfortably; hundreds of megabytes of scans can strain a phone. When in doubt, merge in two passes.
Are my PDFs uploaded to a server?
No. pdf-lib runs in your browser; the files are read and combined locally and never transmitted.