Are my PDF files uploaded to a server?

No. This tool merges your PDFs entirely inside your browser using the pdf-lib library. The files are read from your device, combined in memory, and the result is generated locally — nothing is ever sent over the network. That makes it safe for contracts, payslips, medical records and other private documents.

How many PDFs can I merge at once?

There is no fixed limit — you can add dozens of files. The practical ceiling is your device's memory, because the entire merge happens locally. Merging a handful of normal documents (a few hundred pages total) is instant; very large scanned PDFs use more RAM, so combine those in smaller batches if your browser slows down.

Can I change the order of the pages?

Yes. Each file appears as a row you can drag up or down to reorder, and there are arrow buttons for precise moves. The merged PDF keeps the files in exactly the order shown in the list, so you control which document comes first, second, and so on.

Will merging reduce the quality of my PDFs?

No. Pages are copied losslessly from each source file into the new document, so text stays selectable, images keep their original resolution, and vector graphics remain sharp. Merging only joins the pages together — it does not re-compress or downscale anything.

Can it merge password-protected PDFs?

It can read and merge PDFs that only have permission restrictions (such as no-print flags), but it cannot open files locked with an open password. If a file is password-protected to open, remove the password in your PDF reader first, then merge the unlocked copy here.

Does it work offline and on mobile?

Yes. Because all the work is done in your browser, the merger keeps working even with no internet connection once the page has loaded, and it runs on phones and tablets as well as desktops. The drag-to-reorder list and arrow buttons both work with touch.

Merge PDF — Gera Tools

Merge PDF combines several PDF files into a single document — entirely inside your browser. Drop in your files, drag them into the order you want, give the result a name, and download one merged PDF. It is built for anyone who needs to staple together a set of documents: a scanned contract plus its appendices, an invoice plus its receipts, a portfolio of pages exported one at a time, or a stack of forms that belong in one file. Because nothing is uploaded, it is safe for the documents you would never want to send to a stranger’s server.

How it works

When you add files, the tool reads each one with the browser’s FileReader API and parses it with pdf-lib, a pure-JavaScript PDF library. That parsing step lets it show you the page count and file size of every PDF before you commit to anything, so you can confirm you have the right files and the right number of pages.

The list you see is fully reorderable. Each row can be dragged up or down, and there are arrow buttons for precise, one-step moves — handy on touchscreens. The order in the list is the order in the final document, so the file at the top becomes the first pages of the merged PDF.

When you press Merge, the tool creates a brand-new, empty PDF and copies every page from each source file into it, in order, using pdf-lib’s copyPages. This is a lossless copy: selectable text stays selectable, images keep their resolution, and vector graphics stay sharp — nothing is re-compressed. The finished document is handed to you as a download. At no point does any byte of your files travel over the network, which is something upload-based competitors architecturally cannot offer.

Example

Say you have three files from a job application: cv.pdf (2 pages), cover-letter.pdf (1 page) and references.pdf (3 pages), and you want to send them as one attachment.

Drop all three onto the box. The list shows cv.pdf · 2p, cover-letter.pdf · 1p, references.pdf · 3p — 6 pages total.
Drag cover-letter.pdf to the top so the letter leads.
Name the output application and press Merge 3 PDFs.

You download a single application.pdf with all 6 pages in the order cover letter → CV → references. The original files are untouched, and nothing left your laptop.

Files added	Pages each	Output
2 invoices	1 + 1	1 PDF, 2 pages
3 contract parts	4 + 2 + 6	1 PDF, 12 pages
10 scanned forms	1 each	1 PDF, 10 pages

Every page is copied in your browser — no numbers, names or documents are uploaded or stored.