Merge PDF files online

Combine several PDFs into a single document — free, and without uploading anything.

Files never leave your device Runs in your browser 3 free operations with a free account

Merging is the most common thing people need from a PDF tool: an invoice and its receipt, a contract and its annexes, three scanned pages that should have been one file. LuxSign merges them in the browser using pdf-lib, so the documents stay on your machine the entire time. Everything runs in your browser — the file is never uploaded to a server, so it never leaves your computer.

How to merge pdf files online

1
Add your files
Select or drag in the PDFs you want to combine. You can add as many as you need.
2
Put them in order
Drag the files into the order you want them to appear in the finished document.
3
Merge
Click merge. The combined PDF is assembled locally, in your browser.
4
Download
Save the single merged PDF to your computer.

When you would use this

Combining an invoice with its supporting receipts before filing
Merging a signed contract with its annexes into one archive copy
Joining separately scanned pages into a single document

Questions

Are my files uploaded to a server?

No. Merging happens entirely in your browser using pdf-lib. The PDFs are read into memory on your own device and never transmitted to LuxSign or anyone else.

Is there a limit on how many PDFs I can merge?

There is no fixed limit on the number of files. The practical limit is your device memory, since the documents are processed locally.

Will merging reduce the quality of my PDF?

No. Pages are copied across without re-encoding, so text stays selectable and images keep their original resolution.

Need to sign the document too?

LuxSign signs PDFs with electronic signatures that are legally valid across the EU under eIDAS — from a simple drawn signature through to a qualified electronic signature (QES) made with your eID smartcard, which carries the same legal weight as signing by hand.

See how signing works

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Remove the pages that should not be there.

Add page numbers to a PDF

Number the pages of any document, wherever you need them.