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Merge PDF

Combine as many PDFs as you like into a single document. The files are read and rewritten inside this page — nothing is uploaded.

  • 0 uploads
  • No limits
  • No signup
  • Works offline

Why do this locally

A merged PDF is usually a merged something private. Scanned passports for a visa application. Bank statements for a mortgage. A medical file for a second opinion. Signed contracts.

Every server-based merge tool asks you to upload all of that, trust a privacy policy you did not read, and hope the deletion schedule is honoured. Some of them are entirely trustworthy. You have no way to tell which.

This page removes the question. The merge runs in your browser with pdf-lib, a pure-JavaScript PDF library. Your files are read from disk into the tab’s memory, recombined, and written back out as a download. There is no server component to trust, because there is no server component.

What actually happens to the pages

pdf-lib does a structural copy rather than a re-render. For each source document it:

  1. Parses the cross-reference table and object graph.
  2. Copies the page objects you asked for, along with everything they depend on — fonts, embedded images, colour profiles, XObjects.
  3. Deduplicates shared resources so the output is not needlessly large.
  4. Writes a fresh document with a single, consistent object stream.

The practical consequence is that quality is untouched. A 300 dpi scan is still a 300 dpi scan; a vector chart is still vector. It also means the output is often smaller than the sum of its inputs, because repeated fonts get stored once.

Ordering

The list is the document. Whatever order the rows are in when you press merge is the order the pages appear.

Files land in the list in the order you dropped or selected them, which for a multi-select in your file manager is usually alphabetical. If you name scans 01-front.pdf, 02-back.pdf and so on, they will already be correct. Otherwise the ↑ and ↓ buttons on each row move it, and they are reachable by keyboard.

Common situations

Combining scans of a multi-page document. Most flatbed scanners produce one PDF per page. Drop them all in, check the order, merge.

Assembling an application pack. Passport, photo, proof of address, bank statement. If some of those are photos rather than PDFs, run them through JPG to PDF first — the result screen there hands the new PDF straight to this tool.

Putting a report back together after signing one page separately. Merge the unsigned front, the signed page and the unsigned back, in that order.

The trade-off, stated plainly

Working locally is not free of downsides. A cloud service can throw a hundred CPU cores at a thousand-page document; your laptop cannot. If you are merging enormous scanned archives, you will feel that. For everything most people actually merge — a handful of documents, tens of pages — local is faster anyway, because you skip the upload entirely.

How it works

  1. 01Add your PDFsDrop them on the page, click to browse, or drop a folder. Up to fifty files at a time works comfortably.
  2. 02Put them in orderUse the ↑ and ↓ buttons on each row. The order in the list is the order in the finished document.
  3. 03Name the outputGive the merged file a sensible name so it does not land in your downloads folder as “merged (3).pdf”.
  4. 04Merge and downloadpdf-lib copies every page into a new document on your device. One click, one file.

Questions people actually ask

Is there a limit on the number of files or pages?
Not an imposed one. Fifty documents and several hundred pages merge without trouble on an ordinary laptop; the real ceiling is how much memory your browser tab is allowed. Because nothing is uploaded, there is no bandwidth cost to ration.
Are my documents uploaded anywhere?
No. The merge is performed by pdf-lib, a JavaScript library running inside your browser tab. You can watch the Network tab in developer tools during a merge and see that no request carrying your document is made. This matters more than usual for PDFs, which tend to be contracts, medical records and bank statements.
One of my files is password-protected and it failed.
Encrypted PDFs cannot be read without their password, and this tool does not attempt to bypass encryption. Open the document in a PDF reader with the password, save an unprotected copy, and merge that.
Does merging reduce quality?
No. Pages are copied object by object into the new document — the same fonts, the same images, the same vector content. Nothing is re-rendered or re-compressed.
Will the merged file keep bookmarks, links and form fields?
Internal page content, images and annotations are preserved. Document-level structures such as outlines (bookmarks) and interactive form fields are not carried across reliably when pages move between documents — if you depend on a fillable form, merge with care and check the result.
Can I pick specific pages rather than the whole file?
Not yet in this release. Page-level selection, deletion, rotation and reordering land with the PDF Organiser. For now, split what you need with another tool or merge whole documents.
Does it work offline?
Yes. Once the page has been visited, the service worker keeps everything needed, and merging works with the connection off entirely.

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