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Merge PDF

Combine several PDFs into one file, in your chosen order, entirely in your browser.

Privacy: your files never leave your device. All processing happens locally in your browser.

How to use

  1. 1.Click Browse PDFs and select two or more PDF files, or drag them onto the page.
  2. 2.Reorder files with the up and down arrows and remove any you do not need until the order is right.
  3. 3.Download the merged PDF from the result link — everything is combined locally in your browser.

About Merge PDF

Merge PDF combines two or more PDF documents into one single file, and it does the entire job inside your web browser. There is no upload step, no server round-trip, and no account required. The moment you pick your files, they are read into memory on your own device, merged locally, and offered back to you as a download link. Nothing you touch ever leaves your computer, which makes this tool safe to use with contracts, invoices, tax paperwork, medical forms, and any other sensitive material you would never want sitting on a stranger's server.

Under the hood the tool uses pdf-lib, a mature open-source JavaScript library that reads and writes PDF documents directly in the browser. For each file you add, the tool loads the document, copies every page object exactly as it exists in the source, and appends those pages to a fresh output document. Because pages are copied rather than re-rendered or re-encoded, your text stays selectable, your vector graphics stay crisp, and your embedded images keep their original quality. The merge is lossless — the output is a faithful concatenation of your inputs, not a flattened screenshot of them.

Order is completely under your control. Every file you add appears as a row showing its name and page count. Use the up and down arrows to reorder files until the sequence is exactly what you want, and remove any file with a single click. A running total shows how many pages the finished PDF will contain, so you always know what you are about to download before you download it. The tool only produces an output once you have at least two valid PDFs in the list, because merging a single file has nothing to combine.

There is no hard page limit and no file-count limit imposed by the tool itself. The only real ceiling is your device's available memory, since every file is held in RAM while it is merged. In practice this comfortably handles dozens of everyday documents and hundreds of pages on a normal laptop.

Password-protected and encrypted PDFs are the one case the tool cannot merge directly. When a file is locked, the underlying library refuses to read its pages, so the tool skips that file and tells you clearly which one needs attention. To include a protected PDF, first remove its password using the application that created it or a dedicated unlock tool, then add the now-unprotected copy here. This is deliberate: forcing a locked document open can silently corrupt the merged result, so the tool never attempts it.

Because everything runs client-side, the merge is fast and works offline once the page has loaded. There are no queues, no watermarks, and no size tiers gated behind a paywall. Whether you are stitching together scanned receipts, assembling a multi-chapter report, combining signed agreement pages, or building a single portfolio from separate exports, Merge PDF gives you a private, instant, and lossless way to turn many PDFs into one.

Frequently asked questions

Are my PDF files uploaded to a server?
No. Every file is read and merged entirely inside your browser using JavaScript. Nothing is uploaded, stored, or sent anywhere, so even sensitive documents stay private on your own device.
Why can't I merge a password-protected PDF?
Encrypted or password-protected PDFs cannot be read without the password, so the tool skips them and tells you which file is locked. Remove the protection in the app that created the file first, then add the unprotected copy and merge again.
Is there a limit on how many PDFs or pages I can merge?
The tool sets no fixed limit on files or pages. The only practical ceiling is your device's memory, since each PDF is held in RAM while merging. Most laptops handle dozens of files and hundreds of pages with ease.

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