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Merge PDF offline — no internet, no uploading

This merger genuinely works offline: load the page once, switch off your WiFi, and it still combines PDFs — proof that your files are processed on your device and not on a server. That distinction matters when the documents are salary slips, legal notices or medical reports you have been told never to upload, or when you are on a train with patchy data and a deadline.

  • No upload — files stay on your device
  • Works offline once loaded
  • Free forever, no signup, no watermark
Drop two or more PDFs here, or tap to choose Contracts and statements are safe — merging happens on your device, nothing is uploaded
Files to merge, in order
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Add at least two readable PDFs to merge.

Merging… {{ progress }}%
  • Files merged {{ readyItems.length }}
  • Total pages {{ totalPages }}
  • Merged size {{ resultSizeLabel }}

Pages were copied losslessly — nothing was recompressed, and nothing left your device.

How to use this tool

  1. Open the page once while online

    The page and its open-source PDF engine load into your browser. From that point the network is not needed — you can even go into flight mode.

  2. Add your PDFs and order them

    Drop the files in and drag the cards into reading order. Page counts and sizes are read locally.

  3. Merge and save

    The combined PDF is assembled in your browser's memory and downloads straight to your device — no network request is made at any point.

Questions people ask

How can a website merge PDFs without internet?

The merging code is ordinary JavaScript that runs inside your browser, like a calculator app. Once the page has loaded, everything it needs is already on your device — the internet was only needed to deliver the page itself.

How do I verify nothing is uploaded?

Two ways: turn off WiFi after the page loads and merge anyway, or open your browser's developer tools on the Network tab while merging — you will see zero requests carrying your file.

Why does offline merging matter for confidential files?

Many workplaces, law firms and banks prohibit uploading client documents to third-party websites. An in-browser merger never transmits the file, so combining a case bundle or a KYC packet here does not breach that rule the way a server-based tool would.

Do I need to install anything?

No. There is no app, extension or desktop software — the browser you already have does the work. That also means nothing to uninstall and no installer permissions to worry about.

Is there a limit on file count or size when offline?

The same as online: none imposed by us. Your device's memory is the ceiling — merging a few hundred megabytes works on most phones made in the last five years.

Will the merged file be identical in quality?

Yes — pages are copied byte-for-byte into the new document, never re-rendered, so fonts, images and form fields on each page stay exactly as they were.

Related tools

Free because it costs us nothing to run: your browser does the work, not our servers. Made by Dynamb Technologies — we build software for businesses.